SOUTH ORANGE - An arrest warrant was issued Monday for a former Seton Hall student after a bomb threat at the university last week.

Acting Essex County Prosecutor Carolyn Murray and South Orange Police Chief James Chelel say they arrested Dennis Mamrosz, 24, who is already incarcerated in Yonkers on unrelated charges.

Police say a tipster gave them a copy of a threatening email on Thursday.

Essex County Sheriff Armando Fontoura says the department's K-9 unit spent several hours checking the Seton Hall campus Thursday. No bombs or explosives were found.

Authorities say Mamrosz had not been a student at Seton Hall since 2010 and did not graduate. He was not in jail at the time of the threat.

Mamrosz is charged with making terrorist threats. Bail was set at $20,000.

The suspect will be extradited once he faces the unrelated charges in New York.