Police are searching for a suspect who allegedly stabbed a Los Angeles Metro Bus operator multiple times Wednesday evening, leaving him in critical condition.

A male suspect boarded the bus in Woodland Hills and began arguing with the driver before stabbing him, Metro Los Angeles said on Twitter. The suspect then fled on foot, officials said.

L.A. Police Department officers began a grid search of the area, Chief Michel Moore said. Police officials released a statement with images of the suspect.

“This heinous act of violence is horrific and the harm done to one of our Metro drivers is tragic. I join the entire City family in praying for him tonight, and my heart also goes out to his family," Mayor Karen Bass said in a statement.

This is a developing story. Please check back for updates.