A head-on crash Sunday night that killed two people have been caused by vehicles racing west on Constitution Avenue near Circle Drive, Colorado Springs police said Monday.

A westbound Mazda sedan that was apparently racing another vehicle about 8:30 p.m. Sunday went out of control and and struck an eastbound Toyota head-on near Winston Road, police said. The Mazda was driven by a 25-year-old woman, who died at Memorial Hospital, police said.

The driver of the Toyota, an 83-year-old woman, died at the scene, said police Lt. Brian Ritz.

The identities of the drivers have not been released by police.

Traffic on Constitution Avenue and North Circle Drive was shut down until 11:30 p.m. Sunday.