UNION CITY >> One person was killed and another was seriously injured in back-to-back traffic collisions Tuesday night in Union City, according to authorities.

The collisions happened around 8:50 p.m. on Dyer Street near Cabello Drive, the Union City Police Department said in a news release.

A driver initially hit a pedestrian; when the driver went to check on the welfare of the pedestrian, the driver and the pedestrian were hit by a second driver, police said.

Officers arrived to find the pedestrian and the first driver suffering from major injuries.

The pedestrian, an elderly woman, was pronounced dead at the scene. The Alameda County Coroner’s Bureau identified her as Evelyn Simangan, 81, of Union City.

Police said the first driver was taken to an area hospital, where he appeared to be in stable condition.

The second driver stopped at the scene and cooperated with the Police Department’s investigation. The drivers did not appear to be under the influence of drugs or alcohol.

“The Union City Police Department understands that this is a tragic incident for everyone involved and would like to express our condolences to the families impacted by this incident,” police said.

Anyone with information related to the case can contact Officer Toscano at 510-675-5292.

Staff writer Harry Harris contributed to this report.