Three Columbia teen-agers were charged yesterday in connection with a series of explosions earlier this month that damaged two cars, blew up a mailbox and flattened the front door of a house, county police said.
Police said the explosions, which occurred on Jan. 10 and 11, were caused by pipe bombs and explosive "quarterstick" charges, most of which were home-made.
An 18-year-old Howard High School student, Gregory H. DeGrafft of the 9300 block of Wild Bees Court, was charged with possessing a pipe bomb, manufacturing explosives without a license and two counts of destruction of property.
He and the other suspects, Martin Thomas Sokoloski, 18, of the 5500 block of Phelps Luck Drive, and Curt H. Seiler, 19, who has been living at the Sokoloski's home, were arrested after investigators raided their homes yesterday morning.
Mr. Sokoloski, who was arrested in his dormitory at the University of Maryland, was charged with possession of a pipe bomb that was found in his bedroom at his family's home, police said.
Bomb charges also are pending against Mr. Seiler, who was arrested at the Sokoloski's home and charged in an unrelated assault.
County police Sgt. Gary L. Gardner said the suspects, who are friends, were believed to have been drinking before the explosions, which damaged property but caused no injuries.
"They were apparently riding around drinking and looking for something to do," Sergeant Gardner said.
The first two incidents were reported in or near the Columbia Palace 9 movie theater parking lot about 9 p.m. Jan. 10. A car windshield was blown out and a mailbox blown up.
After midnight, a pipe bomb was detonated beneath another car in the 5700 block of Yellow Rose Court in Columbia, causing heavy damage and flattening the tires.
The final explosion was on the front porch of a home in the 5500 block of Foxtail Lane in Ellicott City. The blast forced in the front door and blew out a front window.
Police said they believe the youths picked the first three sites at random. The Foxtail Lane explosion is believed to have been retaliation against another teen-ager who lives there and who had previously filed an assault charge against Mr. Seiler, police said.
Recovered in the searches were numerous items that are used for explosives.