With the city planning to close the 30th Street Men’s Shelter on First Avenue, throngs of homeless men – some of whom are mentally ill, substance abusers, and/or sexual offenders – are slated to be moved into the Lexington Avenue Armory between 25th and 26th streets.

The plan has elicited expressions of anger or frustration among politicians, community activists, and residents of the area, which is home to many schools.

Rumors have been swirling around that more than 30 of the residents in the current men’s shelter are Level III sexual offenders, considered the most dangerous of the three classes, said Antoinette Carlina, the district manager for Community Board 6, where the men’s shelter currently exists. However, although there were 35 such offenders listed on the New York State Division of Criminal Justice Services’ Sex Offender Registry as residing in the shelter last month, only three were actually living there, the associate commissioner of communications for the Department of Homeless Services, James Anderson, said.

City Council Member Margarita Lopez, whose district includes the armory, at 68 Lexington Ave., said she was outraged that the city’s Department of Homeless Services would close one neighborhood facility to replace it with another. She said the men’s shelter, which abuts her district, has long posed a problem to her constituents because the clients spill out and wander the streets of her district. The Department of Homeless Services proposes to soon move 120 beds from the men’s center into what until June had been the site of a women’s shelter for more 20 years.

Forty of the men’s beds would be eliminated in the conversion process due to what the agency called a de crease in the homeless population. The remaining 300 beds have not yet been accounted for. The men’s center serves as the intake point into the system for single men. It is not clear where the intake will eventually take place.

“We see it as a positive for the homeless and for the community,” Mr. Anderson said. The agency plans to hire social workers for the new facility, integrate a homeless prevention program, and place peace officers – who have arrest powers – in the facility. The city has sought to shut down the men’s shelter for about eight years. It took a step forward this summer when it moved about half of its 850 beds to an East Williamsburg facility operated by the Doe Fund.

Plans to move into the armory are not definitive. “We are currently reviewing DHS’s proposal,” said Ken Kisselbrack, the director of public affairs for the state’s Division of Military and Naval Affairs, the proprietor of the armory.

Many activists have said the homeless services department has been less than forthcoming about its intentions.

Complaints have been filtering into the offices of politicians and activists by the dozens. Ms. Lopez’s office has received about 100, she said. The office of Council Member Eva Moskowitz – whose district includes the men’s shelter – has received 25 complaints since the end of July, said her director of community affairs, Jennifer Sedlis. The complaints have mainly been appeals to stop the transformation of the armory into a men’s homeless shelter, Ms. Sedlis said.

David Diamond, chairman of Board 5 – in which the armory is located – said there have been 36 complaints since July 15, plus a petition signed by more than 100 people in a cooperative across the street from the armory. Hundreds have been made to Community Board 6. Even more have been made to other community associations.