Matthew Tollis, who police say admitted to participating in at least six so-called "swatting" hoax calls this year, was released on $100,000 bail today after appearing in federal court.

Tollis, 21, of Wethersfield, Connecticut, is accused of calling in false emergencies that sent heavily armed cops to a school or home. He could face 15 years in prison if convicted.

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Tollis was arrested Sept. 3 for his alleged role in the April 3 swatting call that claimed there was a bomb at the University of Connecticut. He is charged with three counts connected to the UConn incident as well as three counts of federal conspiracy and aiding and abetting.

Authorities said Tollis was just one in an international ring of so-called "swatters" who call themselves TeAM Crucifix or Die. The pranksters disguise their phone numbers and then call 911, triggering SWAT.

An affidavit filed in federal court said that swatting was often perpetrated by X-Box gamers who occasionally hijacked people's Twitter or Facebook accounts and then refuse to release them unless the victims make a swatting call.

According to the affidavit, one of those calls made by members of TeAM Crucifix or Die was directed at the recently reopened Sandy Hook Elementary School in Newtown, Connecticut, the site of the 2012 massacre of staff and first graders.

The FBI said there are more than 400 swatting attacks a year, each costing thousands of dollars in taxpayer money. Authorities continue to search for others in the ring.

Tollis' attorney Jeremy Weingast had no comment on Friday before Tollis was due in federal court.