A self-described “amateur comedian” charged with a threat that locked down Southern New Hampshire University for about an hour on Wednesday, Oct. 28, is headed back to New Hampshire Hospital to await trial, say prosecutors.

Shawn DeCoste, 31, of Derry was arraigned on criminal threatening and disorderly conduct charges Oct. 29 in Salem District Court via a televised feed from Rockingham County jail.

DeCoste’s Oct. 28 arrest was prompted by a telephone call between the accused and Linda Richelson, director of SNHU’s Salem center, about 4 p.m.

Informed he was being expelled, DeCoste, a graduate student, allegedly said, “I am going to make you regret your decision for the rest of your life,” according to the arrest affidavit and criminal complaint.

The conversation prompted university officials to close the 19 Keewaydin Drive campus for about an hour as police cleared and secured the building. Police arrested DeCoste at his 109 Franklin St. home about 7:45 p.m.

In court yesterday, prosecutor Robert Prince said DeCoste was on conditional release from the state hospital and officials there want him returned.

Opened in 1842, the Concord- based state hospital is publicly funded and provides psychiatric and neurological care. Police didn’t know why DeCoste is a patient of the state hospital, and officials there did not respond to requests for information.

Capt. Shawn Patten of the Salem Police Department would not elaborate on what DeCoste allegedly told Richelson, but said the nature of the threat was “against her health and well-being.”

In his arrest warrant affidavit, Officer Daniel J. Nelson wrote, “I concluded that Richelson was in fact fearful of harm from DeCoste. The threats made by DeCoste had in fact caused great alarm and concern for the safety of both the school and the persons within.”

DeCoste was charged with resisting arrest after a struggle with Derry and Salem police during which he claimed “diplomatic immunity,” police said.

DeCoste was held overnight at a county jail on a $25,000 cash bail, police said. During his arraignment, DeCoste told the court he has lived alone for the past four years and was an amateur comedian.

“I don’t get paid, but I keep a busy schedule,” he said.

On his MySpace profile, DeCoste has posted several videos of his stand-up routine and says he is a 2009 graduate of Hesser College.

He describes himself as “nice and serious” and a “certified genius like Einstein.”

The court decided DeCoste should continue to be held on $25,000 cash bail, but will be returned to the state hospital, Patten said. The court set his trial date for Nov. 23.