The 22-year-old student who strode across the Queens campus of St. John’s University on Wednesday wearing a mask and carrying a loaded rifle suffers from severe mental illness and had no intention of harming anyone, his lawyer said yesterday.

The student, Omesh Hiraman, was confined yesterday at Bellevue Hospital Center in Manhattan. He will be arraigned today at his bedside on charges including fourth-degree criminal possession of a weapon, Richard A. Brown, the Queens district attorney, said in a news release.

Mr. Hiraman was subdued and arrested on the St. John’s campus at 2:30 p.m. Wednesday after students and faculty had been instructed in cellphone text messages to remain indoors, effectively bringing the campus to a standstill.

Anthony J. Colleluori, the lawyer, who spoke at a news conference, said Mr. Hiraman was diagnosed with schizophrenia in 2003 while attending Cornell University and was treated at Mount Sinai Medical Center in Manhattan. According to Cornell, Mr. Hiraman left without graduating in the spring of 2005. Simeon Moss, a spokesman for Cornell, said the university was bound by federal privacy laws not to comment on why Mr. Hiraman left.

Mr. Moss said Cornell “will do everything within the bounds of the law to cooperate with another institution” when a student who intends to transfer is believed to have severe mental problems and could become violent. In the case of Mr. Hiraman, there was no communication between Cornell and St. John’s. Mr. Hiraman did not ask to transfer his academic credits from Cornell, and began anew as a St. John’s freshman this year.

Dominic Scianna, a spokesman for St. John’s, said, “We were not aware of any behavior problems.”

The description of Mr. Hiraman’s mental state came as the police and university officials yesterday sought signs that might have predicted his bizarre behavior on campus. The officials, and people who knew Mr. Hiraman, provided a portrait of a studious, introverted young man who had suffered academic setbacks but showed little inclination toward violence.

Mr. Hiraman, who has been living his with parents in Elmhurst, grew up in a competitive environment in which academic success was demanded, according to acquaintances. He has two older brothers, a physician and an engineer, and a younger sister who is still living at home.

But after graduating from Stuyvesant High School, Mr. Hiraman faltered after he entered Cornell to study engineering in 2002.

“There is nothing we can identify at this point that happened at St. John’s that should have raised a red flag,” said Police Commissioner Raymond W. Kelly. He said detectives had found no notes or recordings in which Mr. Hiraman warned of his behavior in advance, and no evidence that he had argued with fellow students or faculty members.

Mr. Kelly said that detectives were seeking a search warrant for Mr. Hiraman’s computer, but that they had not yet obtained the warrant late yesterday.

Mr. Hiraman’s mental condition was aggravated in recent weeks after he had back surgery, Mr. Colleluori said. In an adverse reaction to pain medication, he said, Mr. Hiraman vomited repeatedly, and had difficulty digesting the medication that he needs to control the symptoms of his mental illness.

“I believe he has been undermedicated for the schizophrenia,” said Mr. Colleluori, who was joined at the news conference by Mr. Hiraman’s parents, Pat and Vejai Hiraman.

One thing Mr. Hiraman may have signaled was his intention to acquire a gun, if not to use it. In June — several weeks before his back surgery — he walked unannounced into a lawyer’s office in Jackson Heights, introduced himself as a student doing research on gun control, and asked what procedures he must follow to obtain a gun.

“He seemed like a normal student, but a little more assertive than most,” said Michael Paul, the lawyer, who ultimately exchanged e-mail messages with Mr. Hiraman, but said yesterday that he did not offer advice on how Mr. Hiraman might get a gun. “He came walking right into the inner office.”

Investigators said yesterday that the gun Mr. Hiraman ultimately purchased about a week ago for $175 at Dick’s Sporting Goods in Poughkeepsie was an uncommon, single-shot, .50-caliber “black powder” rifle that he was able to buy without showing a New York City gun permit.

Bruce Lambert contributed reporting.

Published: September 28, 2007