NEW YORK (AP) - The suspect in the deaths of four homeless men who were bludgeoned with a metal rod as they were sleeping on New York City streets underwent a psychiatric evaluation and is facing multiple charges, including four counts of murder.

Randy Rodriguez Santos was expected to make his first appearance Sunday in court. The early Saturday attack in New York City's Chinatown also left another homeless man with serious injuries.

Police identified one of the victims as an 83-year-old man and haven't released other information on the victims yet.

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Santos, who is also homeless, was taken into custody Saturday with the weapon in his hands, police said. He has been arrested at least six other times in the past two years, three times on assault charges.

In addition to the murder charges, Santos is also charged with attempted murder and unlawful marijuana possession.

It is unclear if he has an attorney.

The gruesome attacks left blood splattered on the doorways and sidewalks where the men had been sleeping, including The Bowery, which has long been a location where those living on the streets have made their nighttime resting area.

Santos' relatives told The New York Daily News he had a history of drug use since his arrival to the United States from the Dominican Republic a handful of years ago.

His mother, Fioraliza Rodriguez, 55, told the paper she had kicked him out of her home about three years ago, after he assaulted her. But while she said she had been afraid of him, she said she "never thought he would kill someone."