NEW YORK (CBSNewYork/AP) — New York City officials have pledged to increase security at shelters citywide following the fatal stabbing of a resident at a homeless shelter.

Mayor Bill de Blasio’s administration announced on Saturday that more peace officers have been deployed to shelters. Those peace officers will be staffed at mental health shelters 24/7, the city said.

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NYPD and Department of Homeless Services officers were seen patrolling The Boulevard Saturday, the 101 bed shelter on Lexington Avenue where police said former teacher Deven Black was murdered Wednesday night.

The shelter houses men with mental health issues. Jeffrey Martin, who has lived at the shelter since November, welcomes the security changes.

“I like it because it makes me feel safer,” he said. “At least we know they’re concerned with our well-being.”

Police said Black’s roommate, 21-year-old Anthony White, is a suspect in the case. The NYPD said White nearly decapitated the victim after threatening for days to kill someone over his stolen cellphone, CBS2’s Brian Conybeare reported.

Police said White has a history of psychiatric issues. So far, police have not been able to track him down.

Black’s son Jonas said the city needs to do more to protect its vulnerable residents, WCBS 880’s Stephanie Colombini reported.

“This was a tragedy that was entirely preventable,” he said.

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In addition to the enhanced patrols announced Saturday, the city has also directed the NYPD to do security reviews at certain shelters.

Other measures being implemented include new mental health teams at shelters, additional funding for mental health services and improved communication protocols between hospital and homeless agencies to target difficult individuals.

“The murder of one of our shelter residents is shocking and disturbing and we must address shelter security with urgency,” said de Blasio. “Our shelters should be safe environments where homeless people, with and without mental illness, can be treated with respect, become self-sufficient and move to permanent housing.”

The announcement came just 24 hours after CBS2 consultant and former Department of Homeless Services Deputy Commissioner Robert Mascali suggested “that the NYPD go in and do a security assessment of every shelter.”

While the mayor’s announcement stops short of doing that at all homeless shelters citywide, the new measures will be instituted at The Boulevard and 27 other shelters for the mentally ill, Conybeare reported.

Manhattan Borough President Gale Brewer told 1010 WINS the murder shows the clear need for more mental health services.

“It’s really, really important to have extensive mental health support. Obviously not only in the shelters, but we need them in the jails, we need wellness support and social workers in our schools,” she said. “We need to dramatically increase the mental health support around our city.”

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