Officer Ray Heim, a 12-year-veteran of the Philadelphia Police Department, is still recovering from head and leg injuries at Albert Einstein Medical Center after a car accident in Logan Wednesday that left him critically injured, police said.

Heim, 40, who is assigned to the 39th District, was hospitalized along with two other undercover officers when the unmarked car they were riding in was hit by a black Pontiac Grand Prix on 18th Street near Windrim about 2:35 p.m.

One of the officers who was less seriously injured had been released as of Thursday night, and the third officer was still hospitalized in stable condition, Officer Tanya Little, a police spokeswoman, said.

Charges have not been filed against the driver who hit the undercover cops, and the cause of the crash is still under investigation, Little said.