Authorities in New York City and the nation’s capital appealed for help Monday in an urgent search for a gunman who has been stalking homeless men asleep on their streets, killing at least two people and wounding three others in less than two weeks.

The mayors of two of the country’s largest cities vowed to swiftly apprehend the suspect with help from civilian tips and surveillance photographs, including one snapshot of the suspect's face released by police at a news conference Monday.

“We know that our unsheltered residents already face a lot of daily dangers and it is unconscionable that anybody would target this vulnerable population,” said the mayor of Washington, D.C., Muriel Bowser, during the news conference in her city.

New York City Mayor Eric Adams, who joined Bowser at the press conference, said the gunman is carrying out his attacks in a premediated manner.

“He looked around. He made sure no one was there. And he intentionally took the life of an innocent person," Adams said.

The killer's motive - if any - was unknown. Authorities have turned their attention to trying to offer what protections they can to homeless people who might become targets.

Adams said New York City police and homeless outreach teams would focus on finding unhoused people in the subways and other locations to urge them to seek refuge at city-owned shelters.

In Washington, city outreach workers were passing out flyers among the homeless population, urging people to “be vigilant” and featuring multiple pictures of the suspect.

D.C. Police Chief Robert J. Contee said there was ballistic evidence tying the shootings in the two cities, adding that one of his homicide captains - a former resident of New York City - began investigating a link while scrolling through social media over the weekend and noticing similarities between surveillance photos obtained by New York City police and his own department.

“Our reach is far and wide, and we’re coming for you,” Contee said at the news conference, speaking directly to the suspect.

The latest violence underscored the urgency to get the homeless off the streets and into safe housing, said Jacquelyn Simone, the policy director for the Coalition for the Homeless in New York City.

“The reason that these people were attacked is because they didn’t have that safety of permanent housing," she said. “And that’s why we really need to use these tragedies as an opportunity to redouble our efforts to ensure that people have a better option than the streets where they’re exposed to both the elements as well as people who might wish to do them harm.”

The earliest known shooting happened at around 4 a.m. on March 3 in Washington D.C., police said, when a man was shot and wounded in the city's Northeast section. A second man was wounded on March 8, just before 1:30 a.m.

At 3 a.m. the next day, March 9, police and firefighters found a dead man inside a burning tent. A subsequent autopsy revealed that the man had died of multiple stab and gunshot wounds.

The killer then apparently traveled north to New York City, police said.

At 4:30 a.m. Saturday, a 38-year-old man sleeping on the street in Manhattan not far from the entrance to the Holland Tunnel was shot in his right arm as he slept.

The victim screamed and the gunman fled, police said.

About 90 minutes later, the gunman fatally shot another man on Lafayette Street in SoHo, police said. The man's body was found in his sleeping bag just before 5 p.m. Saturday.

“Any one of us who’s homeless could have went to that same situation,” said Kess Abraham, who fell into homelessness last month.

After finding refuge in parks and other places across Brooklyn and Manhattan, Abraham tried to find help at the Bowery Mission, which houses hundreds of homeless people in its facilities across the city.

He said he was “pained” to learn of “a guy who lived on the streets who probably was minding his own business getting murdered for no reason.”

Joel Castillo, a 24-year-old experiencing a first brush with homelessness who was also at the mission's downtown facility, said more should be done to keep the city's residents safe - homeless or otherwise.

“I don’t know if it’s a police problem, but given the circumstances, the police should actually kind of step up and do a little bit more. I’m not saying that they don’t already do enough,” he said, “but what I am saying is that there should be a lot more measures taken to ensure that the city’s taxpayers are kept safe.”

James Winans, the mission’s chief executive officer, said staff members are “very concerned about the safety of our neighbors who are without homes."

“It’s very sobering to have experienced this where somebody was killed just three blocks away from our emergency shelter, somebody who was sleeping outdoors," Winans said.

The latest attacks were reminiscent of the beating deaths of four homeless men as they slept on the streets in New York's Chinatown in the fall of 2019. Another homeless man, Randy Santos, has pleaded not guilty to murder charges in those attacks.

A year ago, four people were stabbed in New York City, two fatally, by a man who randomly attacked homeless people in the subway system. That assailant, who was also homeless, is awaiting trial.

New York City's mayor has come under fire for his plan to remove homeless people from the city's subway system by deploying police and mental health workers to keep people from sleeping on trains and subway stations.

Adams has said homelessness was a complicated issue, exacerbated by the pandemic, the economic downturn and mental health challenges.

New York Gov. Kathy Hochul has said the state was working to get more psychiatric beds at hospitals available by increasing the amount of money hospitals receive for having the beds.

By BOBBY CAINA CALVAN and ASHRAF KHALIL

Ashraf Khalil reported from Washington, D.C.