The first week of school in Prince William County was marred by echoes of the disturbances from the last school year: two bomb threats at two different high schools.

But in contrast to last year's threats, which came after soon the shootings at Colorado's Columbine High School, there was no ripple of fear through the student body. There were no mass absences.

The students who officials think are responsible will face expulsion hearings. They also could face criminal penalties of up to $2,500 in fines and 10 years in prison.

A bomb threat this time of year "doesn't really surprise us," said Superintendent Edward L. Kelly. "We start getting [bomb threats] around the first week of school and when springtime hits."

The first threat came Tuesday, the first day of school, when a student at Potomac High School asked a new teacher where to get a parking permit, police said.

"So the student said, 'If I don't get a parking sticker, I'm going to blow up this school,' " said Dennis Mangan, county police spokesman.

Antonio Edward Taylor, 18, of Woodbridge, turned himself in to police Thursday and was released on his own recognizance, Mangan said. He is charged with making a bomb threat.

On Wednesday, two teenage boys were charged with making a bomb threat when someone called in a bomb threat to Gar-Field Senior High School from Potomac Mills Mall. Their names have not been released because they are juveniles.

Sgt. Kim Chinn, police spokeswoman, said the teenagers called the threat in around 10:35 a.m. Wednesday. The school traced the call to a pay phone at the mall. Mall guards reviewed their security tapes and were able to identify two suspects, who were subsequently questioned and charged with making a bomb threat.

A 15-year-old, from Dale City, was skipping classes. A 16-year-old, also from Dale City, had been expelled from Gar-Field High.

Gar-Field Principal Roger Dallek said a security team swept the school for possible dangerous devices but found nothing. He said school personnel can be very "persistent" in catching people who call in bomb threats, noting that the call was traced and the teenagers were picked up within hours of making the threat.

"That's the message that these teenagers need to have," Dallek said.

The 15-year-old student now risks being expelled from school. Dallek will make a recommendation to the area associate superintendent, and the School Board will have the final say.

"It's unfortunate for the family," Dallek said. "But in this day and age, it's just not acceptable."

Last school year, 21 students were expelled for making threats of violence at Prince William schools. Eight of those were bomb-related threats. In all, 133 students were expelled last school year.