Sheriff's deputies are still investigating a head-on collision that killed two women, but a 2-year-old passenger has already been released from the hospital.

The 2-year-old grandson of Judy Bjorkman, 56, was treated and released from University of New Mexico Hospital after the two car crash that killed Bjorkman and another driver, Katherin Cullen, 56, Bernalillo County Sheriff's Lt. David Knowles said.

Cullen was driving the wrong way on the westbound lane of I-40 near the Tijeras exit at about 8 p.m. Wednesday, Knowles said. Investigators are still trying to determine when -- and why -- Cullen entered the westbound lanes heading eastbound.

Drugs and alcohol do not appear to be a factor in the accident, Knowles said.