The officer, identified as Luigi Osso, is in critical but stable condition at Westchester Medical Center in Valhalla.
Both the officer's car and the blue Mustang that was the subject of the pursuit were so badly damaged, the drivers had to be cut out of their vehicles.
Published reports say the collision sent the police cruiser spinning several times before crashing into a pole.
"We heard a short skid and a large collision. The officer was completely unconscious and unresponsive. He looked like he was in really bad shape," eyewitness Michael Pelliccio said.
Police say the operator of the stolen vehicle was a 16-year-old boy from Connecticut. At this time, detectives are confirming his identity. He was extricated from his vehicle by the Irvington Volunteer Fire Department and sustained injuries to his back and legs. He transported to the Westchester Medical Center for treatment.
Osso, a 6-year police veteran who served with the Putnam County Sheriff's Office before joining the Irvington Police Department, was tended to by members of the Irvington and Dobbs Ferry Volunteer Ambulance Corp, as well as the Greenburgh Paramedics. Osso was extricated from his vehicle by the Irvington Volunteer Fire Department and transported to the Westchester Medical Center for treatment. Osso sustained severe head trauma and serious injuries to his entire body. He has undergone several surgeries.