PHILADELPHIA (CBS) — A suspect is facing kidnapping charges after police say he carjacked an ambulance at gunpoint with a patient inside.

“It was pretty scary. He was weaving in and out of traffic, on a blowout tire riding on that rim. I thought he was going to flip over,” eyewitness Brian Perkins said.

The incident started on the Schuylkill Expressway just before 3 p.m. Friday afternoon.

Pennsylvania State Police say 25-year-old Brian Timothy Kada Jr., of Philadelphia, walked onto the westbound side of the expressway near Girard Avenue while the ambulance was transporting a patient. Police say Kada pointed a gun at the two operators stuck in rush hour traffic and jumped into the passenger side.

Perkins was on the expressway when he says the ambulance nearly hit him.

“All of the sudden there was an ambulance in my rear view mirror. He’s just coming at me. I pull over to let him by. He swerves, almost clips the front of the car. I notice a blown out tire in the back, and smoke coming out from under the hood,” Perkins said.

Police say Kada drove the ambulance westbound on the expressway before it became disabled near City Avenue.

Kada fled the ambulance on foot and was taken into custody by police.

The patient inside the ambulance was unharmed and taken to a local hospital.

Kada is facing several charges including Robbery of Motor Vehicle, Kidnapping, assault, violations of the Uniform Firearms Act and other related offenses.

Anyone with information is asked to call Pennsylvania State Police at 215-452-5216.