By Christina Hager | WBZ-TV | October 18, 2012

BOSTON (CBS) – MBTA police are looking for a man who punched a bus driver at 5:40 Thursday morning. Chief Joseph O’Connor says the man wanted the driver to let him out in a spot that was not an actual bus stop. When the driver refused, he hit him in the face and jumped out a window.

It’s the latest in a string of assaults on MBTA bus drivers. Tuesday night, 38-year-old Carlos Ramirez-Rodrigue was arrested for allegedly spitting on the driver.

Last week, surveillance cameras caught two separate incidents in which passengers spit on drivers.

“Quite often, they start with disputes over fare collection and they escalate,” says O’Connor. He says there have been 88 assaults on drivers in the last year, which is an increase of 10 percent.

T officials are coming up with new ways to battle the problem. They’ve started collecting DNA from spitting incidents, and they’ve outfitted a third of the fleet with surveillance cameras.

“I would ask people to put themselves in the driver’s seat, and ask how they would feel if they were subjected to anything like that,” says O’Connor.