A man who threatened police officers in calls to 911 was stabbed Friday morning in the Bronx while awaiting a psychological evaluation, according to the city police department.

Police said Joseph Curet was handcuffed in an emergency room at St. Barnabas Hospital in Belmont, with an officer watching him, when Tomas Berroa, 36, walked by and stabbed him in the arm and chest around 5:30 a.m.

The officer arrested Berroa, who was also a patient in the emergency room, according to officials.

Police officials said they are not sure why he attacked Curet, who suffered a collapsed lung because of the stabbing.

Curet has been charged with making terroristic threats and aggravated harassment.

Officials said he threatened police officers in multiple calls to 911, claiming he was going to kill them with an AK-47.

Police said the department traced the calls back to Curet.

His stepfather, Javier Munoz, said he believed he may have been on drugs when he allegedly made the threats.

"He's been in the hospital for detox a couple of times," Munoz said. "But psychologically he's not bad, at all. Probably he gets different when he takes the drugs.

"Whatever he did, if he took drugs and threatens somebody, it's under the drugged state," Munoz added.

Berroa faces an attempted murder charge. He is scheduled to be in court Wednesday.