Although the ’70s and ’80s were known for infamous serial killers, the 1990s also saw some horrific crimes that shocked the nation.

From mass shootings to shocking celebrity deaths, here are some of the most unforgettable crimes of the ’90s.

Infamous serial killer Jeffrey Dahmer murdered his last victim and was caught in 1991.

Foto: Jeffrey Dahmer. Source: Allen Fredrickson/REUTERS

On May 27, 1991, an injured 14-year-old boy was seen running through the streets. When police responded, Jeffrey Dahmer told the officers the boy was his lover and that they had a flight. After the officers returned the boy to Dahmer and escorted them both home, Dahmer killed him. Dahmer went on to kill four more men, bringing his total number of murder victims to 17.

In July that year, Tracy Edwards, a 32-year-old African American man, was seen walking the streets with his hands handcuffed. He brought police officers to Dahmer’s house, which is where he said he was cuffed. When the officers entered the house, they saw photographs of body parts lying around. Dahmer was arrested on the spot.

Dahmer was found guilty and sentenced to 15 consecutive life terms. He was killed in prison by a fellow inmate in 1994.

Dahmer remains one of the nation's most disturbing serial killers. The chilling case became the subject of a 2017 movie, "My Friend Dahmer," based on a graphic novel.

Pablo Escobar, the Colombian drug lord, was shot in 1993 when he was on the run from authorities.

Foto: Pablo Escobar. Source: AP

Pablo Escobar became one of the richest people in the world in the late '80s and early '90s thanks to the cocaine trade that he controlled out of Colombia. His Medellin Cartel was responsible for 80% of the cocaine sent to the US, leaving thousands dead. He became a target for the US and authorities in Colombia, so he went on the run.

On December 2, 1993, Escobar attempted to escape the authorities by running across rooftops in Medellin, but he was killed in a shoot-out. His death marked the end of the country's reign on cocaine.

When Nicole Brown Simpson and Ron Goldman were found dead in 1994, O.J. Simpson was arrested, sparking the trial of the century.

Foto: O.J. Simpson at his trial. Source: AP Photo/Sam Mircovich/Pool

On June 12, 1994, Nicole Brown Simpson was stabbed to death outside her Los Angeles home along with her friend Ron Goldman. Her ex-husband, NFL star O.J. Simpson, quickly became a prime suspect. He was arrested and charged with the two murders after leading police on a televised 60-mile car chase through Los Angeles. When he finally surrendered in his home, Simpson pleaded "absolutely, 100 percent not guilty."

The trial itself became a media frenzy, as Simpson famously tried on the gloves that were left at the murder scene. On October 3 the following year, over 150 million people (57% of the US population at the time) tuned in to hear the verdict. After just two hours of deliberations, Simpson was found not guilty.

The murders of Nicole Brown Simpson and Ron Goldman are still unsolved.

In 1994, Gary Ray Bowles went on an eight-month killing spree and became known as the I-95 Killer.

Foto: Gary Ray Bowles. Source: Florida Department of Corrections

Gary Ray Bowles killed his first victim, John Hardy Roberts, in Daytona Beach in 1994. From there, he murdered five more gay men along Interstate 95, in Maryland, Georgia, Atlanta, and Florida.

At one of his crime scenes, Bowles left a probation document, and he was caught on surveillance camera taking money out of the victim's account. When he was finally caught, he was convicted of three out of the six murders. He was executed by lethal injection in 2019.

While at the height of her career, Latin singer Selena was killed in March 1995.

Foto: Selena. Source: Barbara Laing / Contributor/Getty Images

The month before her murder, Selena Quintanilla was at the height of her career, performing for 60,000 people at the Houston Astrodome. Her album "Amor Prohibido" was nominated at the Grammys for best Mexican-American performance. She was also working on an English album that she hoped would transform her into a crossover hit. By all accounts, she was poised to become the next Gloria Estefan.

But everything changed in March 1995. The year prior, she made Yolanda Saldívar the manager of the Selena fan club and put her in charge of the singer's boutiques. Selena quickly noticed that there were money discrepancies and missing documents with both those businesses. Over the course of a couple of months, Selena confronted Saldívar about the missing documents. Ultimately, those conversations ended with Saldívar shooting Selena after they met at a hotel room. She was 23 years old.

Saldívar was convicted and sentenced to life in prison with no possibility of parole for 30 years. Meanwhile, Selena's song "Dreaming of You" debuted after her death and reached the No. 1 spot on the US Billboard 200 charts.

In 1995, Timothy McVeigh parked a truck filled with explosives in front of a federal building in Oklahoma City, killing 168 people.

Foto: Oklahoma City bombing. Source: AP

On April 19, 1995, Timothy McVeigh rented a Ryder truck that had agricultural fertilizer, diesel fuel, and other chemicals inside of it. He parked the truck in front of the Alfred P. Murrah Federal Building in Oklahoma City and walked to a getaway car. When the bomb went off, it destroyed the building and killed 168 people. Among them, 19 were children.

When the FBI found a rear axle from the truck in the rubble, they quickly traced the piece back to the former US Army solider, McVeigh, who rented the truck. From there, the evidence continued to build against McVeigh: He had traces of chemicals on his clothing, and he even jotted down notes about the bombing beforehand. The FBI also found that two other men knew about the bombing plot and helped him create it.

McVeigh was convicted on 15 counts of murder and was sentenced to death. He was executed in 2001.

A bomb went off at the Summer Olympic Games in Atlanta in 1996, leading to the deaths of two people.

Foto: The Atlanta Centennial Olympic Park. Source: Michael Green/ AP

On July 27, 1996, police received an anonymous phone call, telling them a bomb would go off in 30 minutes at the Centennial Olympic Park in Atlanta. As the location was being evacuated, the bomb went off early. A woman was killed and a cameraman, who was rushing to the scene, also suffered a fatal heart attack. More than 100 more were injured.

At first, security guard Richard Jewell, who found the backpack that held the bomb, was identified as a suspect. Eventually, Jewell was cleared of any wrongdoing.

The crime went unsolved until 1998. A series of bombings that occurred in the South linked Eric Robert Rudolph to the Olympic bombings. He eluded police for several more years and was eventually arrested in 2003. Rudolph was convicted and was sentenced to four consecutive life sentences.

On September 13, 1996, Tupac Shakur was killed in a drive-by shooting in Las Vegas. His rival, Biggie, was murdered in a similar way six months later.

Foto: Tupac Shakur pictured in 1994. Source: Ron Galella/Ron Galella Collection via Getty Images

Tupac Shakur made a name for himself as an acclaimed rapper whose music fought against injustice towards African Americans. Tupac made hit after hit, creating four platinum albums over the course of his career.

But on September 7, 1996, he was seen leaving the MGM Grand Hotel in Las Vegas after getting into a fight. Shakur was in the passenger seat of a car when another car pulled up beside him at a red light, and 13 shots were fired. He died at the hospital on September 13.

Some believed his biggest rival, rapper Christopher Wallace (aka Biggie, Biggie Smalls, or the Notorious B.I.G.) was behind the murder, but he denied any involvement. On March 9, 1997, Biggie was also killed while waiting at a red light.

Since Shakur's death, seven albums have been released under his name, making him one of the best-selling artists of all time.

Over the years, there have been many theories about what happened to the men.

JonBenét Ramsey, a 6-year-old beauty queen, was murdered in 1996, and the case still remains open today.

Foto: JonBenét Ramsey's image is seen on investigators' files. Source: Ray Ng/The LIFE Images Collection via Getty Images/Getty Images

On December 26, 1996, Patsy Ramsey called the police saying her daughter, JonBenét, was missing and that a three-page ransom note was left on the staircase from a kidnapper who demanded $118,000. Despite an exhaustive search, JonBenét's body was found in the basement of the Ramsey home later that day.

From the start, the murder investigation was problematic. John Ramsey had picked up and moved JonBenét's body out of the basement after she was found. John and Patsy were also interviewed together by investigators, which is not typical police procedure. Since the parents gave inconsistent accounts of what happened that night, the public pointed fingers at them.

In 2006, the Ramseys were cleared of any wrongdoing because of advancements in DNA evidence. To this day, no one has been charged with the death of JonBenét.

Famous designer Gianni Versace was assassinated by a serial killer in 1997.

Foto: The mansion where Versace was shot. Source: Alan Diaz/ AP

On July 15, 1997, Gianni Versace returned to his mansion in Miami and was shot by Andrew Cunanan on the front steps. Before the murder, Cunanan was already on the FBI's Most Wanted List after a killing spree where he murdered four men: Jeffrey Trail, David Madson, Lee Miglin, and William Reese.

Once Versace's murder made headlines, a nationwide manhunt ensued. It all came to a head at a houseboat that Cunanan broke into. As police closed in on him, Cunanan killed himself using the same gun he had used on three of his victims. To this day, it's unclear what his motives were.

The famous comedian Phil Hartman was murdered by his wife in 1998.

Foto: Phil Hartman. Source: Ron Galella/Getty Images

Phil Hartman was famous for the eight seasons he spent as a cast member on "Saturday Night Live." While on the show, he was known for his impersonation of President Bill Clinton. He also went on to play a news anchor in the sitcom "NewsRadio."

But the comedian may be best known for his tragic death. On May 28, 1999, Hartman's wife, Brynn, shot the comedian as he laid in bed. As the police arrived at the Los Angeles home, they heard a gunshot as Brynn killed herself.

On April 20, 1999, two students opened fire on their classmates at Columbine High School, killing 13 people and wounding 20 others.

Foto: Columbine High School. Source: Getty Images/Steve Corbis

Around 11 a.m., Dylan Klebold and Eric Harris walked into Columbine High School in Colorado wearing trench coats and placed a bomb in the school cafeteria. They walked back outside to their cars and waited. When the bombs didn't go off, they went back into the school armed with guns and shot their classmates. They killed 12 students and one teacher during their rampage. A little after noon, the pair killed themselves.

Although the motive of the shooters is still unknown, the incident became the most deadly school shooting in history at the time. It also sparked the national conversation around gun control and gun violence.