The house of Susan Welch, dean of the College of the Liberal Arts, and her husband Alan Booth, was damaged Monday by a fire that the State College Police Department is ruling as an arson attack.

The family was not at their 555 Ridge Ave. residence at the time of the fire. Welch was unavailable for comment. Booth, professor of sociology, and his son refused to speak on the matter.

Several neighbors were awakened by the loud explosion and the sound of screeching tires Monday about 12:37 a.m.

"I heard a boom -- an explosion . . ., then the squeaking of tires," said Jacqueline Prybyla of 534 Ridge Ave.

Witnesses saw a car leaving the area at the time of the explosion, said State College Police Chief Tom King in a news release.

Hugh Urban, 550 Ridge Ave., said he went outside to join a crowd of neighbors and saw flames coming from the front door. Only the outline of the door was damaged, he added.

"I was surprised of how limited (the damage) was," Urban said.

Responding police officers observed flames near the front door and the rear of the house, State College police said.

Alpha Fire Company, 400 W. Beaver Ave., quickly extinguished the flames. The house sustained only minor damage, State College police said.

Investigators found no explosive devices in the area and do not believe any such devices were used, police said. Police collected several pieces of evidence from the scene, which will be sent to a crime lab in an attempt to determine the cause of the fire.

An initial investigation has revealed no motive for the fires, and no similar incidents have occurred in the Ridge Avenue area recently.

"The neighborhood is always so calm," Prybyla said, adding, "(Welch and Booth) were really lucky."

Collegian staff writer Kim Burger contributed to this report