Houston Fire Department officials say the ambulance was stolen around 8:30pm while it was responding to a call at a gas station in the 6000 block of Scott Street.
A clerk inside the gas station says he called 911 after the suspect began acting erratically, knocking over displays and threatening employees.
"He said, 'I don't care. I'll kill you. I'll kill you,'" the clerk told Eyewitness News.
HFD responded to the scene, but the suspect, who was described as a psychiatric patient, was still being aggressive so Houston police were called. Before officers could arrive, the suspect ran from paramedics, jumped into the driver's seat of the ambulance and drove off.
He was driving for about 15 minutes before Houston police tracked him to Highway 288 and FM 2234. When they caught up with him and turned on their lights, he pulled over. Police say the suspect wouldn't get out of the driver's seat so they had to forcibly remove him.
"It is a little unusual for somebody that needs help to steal an ambulance from somebody who's trying to help him," said Larry Crowson with the Houston Police Department.
Authorities don't have a motive yet but did say the suspect spit up white chunks that are believed to be crack cocaine.
No one was injured during the chase. However, the ambulance has at least two flat tires.
The suspect faces charges of unauthorized use of motor vehicle and possession of a controlled substance.
Crews shut down the feeder road of Highway 288 just past Shadow Creek during the investigation.
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