GREENSBURG, Pa. -- Former substitute bus driver Paul Lizza, 74, is accused of sexually assaulting six mentally challenged female passengers over a three-year period.

Channel 11 visited Lizza's home on Wednesday, but he refused to talk about the allegations.

Jerry Burke, who lives across the street from Lizza, couldn't believe what he heard about his neighbor.

"It was a shock. I don't believe it. You never know what they're going to say or do. Maybe it never happened you know," said Burke.

Police said Lizza allegedly began assaulting women in January of 2005, and it stopped after the alleged victims complained to police about what happened on the bus.

The women ranged in age from 27 to 52 years old and are moderately to severely disabled.

Police said Lizza would pull the bus off the road into a parking area and sexually molest, fondle or assault one or more of the victims on their way to or from their therapy or training centers.

Burke, who has known Lizza for more than 40 years, said the allegations just don't make sense.

"You know people do lie about stuff and try to incriminate you," said Burke.

Lizza has been charged with six counts of indecent assault and six counts of institutional sexual assault.

He has been released on $5,000 bond and is due back in court in March.

Lizza was a veteran driver for First Student in Westmoreland County. He is no longer an employee.