Thirty years ago, three Metro passengers were killed and 25 injured in the first fatal accident in the history of the subway.

Jan. 13, 1982 was a chaotic and tragic day in Washington. A heavy snowstorm had enveloped the area, and trains and roads were jammed with workers headed home early. Metro, which had opened in 1976, was still relatively new.

Air Florida Flight 90 had just clipped the 14th Street Bridge and plunged into the icy Potomac. Seventy-eight motorists, passengers and crew died in that accident.

Thirty minutes later, the deadly Metro accident occurred about 4:30 p.m., near the Smithsonian station. About 1,200 people were on an Orange Line train headed to New Carrollton when it derailed while backing up from an improperly closed rail switch between the Smithsonian and Federal Triangle stations.

Investigators said a confluence of worker mistakes led to the derailment of a rail car that crushed into a concrete pillar. Two passengers died on impact and a third died later.

The victims included Mildred M. Morgan, 71, and Mary L. O’Meara, 25, coworkers at the Overseas Education Association, and Mariano Cortez, 46, an auditor at the Agriculture Department.

Witnesses Ruth Cannon, 28, of Capitol Heights recalled the scene in The Post in the following days. Cannon said she was standing in the aisle beside the three victims when they died.

“When we hit, everything just crashed in as though the tunnel had caved in,” Cannon said. “We hit so hard. We weren’t going that fast . . . All I saw was glass on top of me. The side of the train was pushed upwards over me. I was taller than the people standing around me; I was just amazed.”

Metro’s in-house investigation of the crash concluded that a wide range of employes committed a series of dangerous errors before and after the accident. Two workers were suspended without pay and barred from returning to jobs that involved operating trains. Metro also changed some of its procedures and issued new instructions to employees.

View Photo Gallery: All but four passengers and one flight attendant of the 79 people aboard died in the crash into the 14th Street bridge over the Potomac River. Here are historic and current photos from the incident.