It has been nearly 20 years since the first mass school shooting in the U.S. -- the shocking tragedy at Columbine High School in Littleton, Colorado, on April 20, 1999. As a “credible” threat ...

On April 20, 1999, two teenage boys dressed in black trench coats went on a killing rampage at Columbine High School in what was at one time the deadliest school shooting in American history.

DENVER (AP) — Hours after she escaped the Columbine High School shooting, 14-year-old Missy Mendo slept between her parents in bed, still wearing the shoes she had on when she fled her math class.

In 1999, Columbine High School, in Littleton, Colorado, faced at the time the largest school shooting in American history. Nearly 20 years later, survivors still suffer debilitating side effects ...

According to CBS News, the parent mentioned the 1999 mass shooting at Columbine High School, one of the most notorious such attacks in the US, which left 13 dead just 8km (5 miles) from Tuesday's ...

April 20 marked the 25th anniversary of the Columbine High School shooting in Colorado, where a pair of gunmen killed 12 students and a teacher before taking their own lives. The attack remains ...

The National School ... Columbine High School massacre in Colorado. Connecticut high school pupil Lane Murdock set up the event in the wake of the Parkland shooting in Florida. Only one hour ...