Rachela Gorodenzik, 51, of Agoura Hills, has been pronounced brain dead by doctors at UCLA Medical Center after being struck by a car Tuesday while walking eastbound on Thousand Oaks Boulevard near Lake Lindero Drive in Agoura Hills, according to officials from the Malibu/Lost Hills Sheriff's Station.

Gorodenzik was to be removed from life support at the medical center, pending the arrival of family members, authorities said.

The alleged driver, Danuda Reczek, 58, also from Agoura, reportedly hit Gorodenzik, who was on her way to a local Pilates class, at about 4:30 p.m., said Sgt. Philip Brooks.

According to Brooks, Recsek said she felt the impact and immediately hit her brakes, but recalled no other details of the incident.

Gorodenzik was treated at the scene and airlifted to UCLA Medical Center, where she was listed in critical condition, authorities said.

Brooks and the collision team were investigating the possibility that Reczek may have accidentally driven onto the sidewalk, or that Gorodenzik may have stepped into the street to walk at some point. No arrest was immediately made.

Brooks was seeking the public's help in investigating the collision.

"If anyone happened to be in the area at 4:25 p.m. yesterday, we’d appreciate a call," he said. "We have one witness that saw the victim walking on the sidewalk in the direction of the Pilates studio. If she was in the street, we don’t know why."

Anyone with information can call Detective David Huelson at 818-878-5556.