Another homeless man came forward Tuesday to say he too was attacked while sleeping, and NYPD officials said they believed Randy Rodriguez Santos — the man accused of viciously beating five homeless men sleeping on Chinatown streets over the weekend, killing four of them — was responsible.

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"The individual was woken up being hit by an object," NYPD Chief of Detectives Dermot Shea said at a crime statistics news conference. "There was a physical confrontation where the individual believes that the possibility exists that he was being attempted to be thrown over the banister, into the water."

Santos is charged with murder and attempted murder for using a piece of metal to beat the sleeping men in the head Saturday morning.

This new case being investigated was reported to police September 27. It happened along the Hudson River near 23rd Street in Chelsea.

"We have him approximately seven blocks away. Very clear video who we believe is Mr. Santos on that evening, and we believe he was responsible for that attack at this point," Shea said.

Santos reportedly has a history of mental health issues and drug abuse.

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"We have him with six arrests and a number of other sealed arrests. I think we have one aided job where he was removed," Police Commissioner James O'Neill said.

Santos was arrested for misdemeanor assault in the Bronx in 2017, but he was not prosecuted because the victim didn't cooperate.

In February of this year, the 24-year-old was arrested for jumping a turnstile in Brooklyn.

He was accused of inappropriate touching at a homeless shelter in Queens in March.

In the Brooklyn and Queens cases, he didn't show back up to court or didn't meet with counselors. Warrants were issued for his arrest. He did spend a few weeks behind bars, but in the Queens case, a nonprofit group posted bail so he could be released.

Mayor Bill de Blasio says it's hard to blame anyone in this tragic case, but says more is being done for homeless people with mental illness.

"The NYPD on our end, we do have the co-response units," O'Neill said. "Where we have two police officers with a mental health professional, that they go out each day and visit people proactively to see that things are continuing to be okay for them and if they are in need of additional assistance."

Detectives want to know if there are other victims out there. They say anyone who thinks they may have been attacked by Santos should contact police.