Rutherford police didn't have to look for the suspect: He turned up at the hospital where the victim was being treated.
The 31-year-old victim apparently let neighbor Joseph Valente, 66, stay at his place after Valente and his girlfriend split up.
After a lengthy stay, the neighbor convinced Valente to take a room at the Extended Stay America just off Route 3, Rutherford Police Capt. Patrick Feliciano said.
They were unpacking Valente's valuables from the trunk of the neighbor's 2017 Lexus when Valente suddenly attacked him, Feliciano said.
The victim held off Valente, seizing the hammer -- but Valente sped away in his car, the captain said.
The victim, whose head was bleeding, was brought to the emergency room at Hackensack University Medical Center, where police spoke with him.
As they were, Valente showed up, Feliciano said.
He apparently had gone to his estranged wife's Bergen County home in Ridgefield and convinced her to drive him to HUMC, the captain explained.
When police asked the victim who attacked him, he pointed to Valente, Feliciano said.
Ridgefield police found the Lexus at Valente's ex-wife's home, he said, adding that Rutherford police found the hammer at the hotel.
Valente was brought to New Bridge Medical Center in Paramus for an evaluation, then was transferred to HUMC for treatment of unknown injuries, records show.
He's charged with carjacking, two counts of aggravated assault, theft and weapons possession -- and also was wanted on an outstanding warrant out of East Orange, records show.
The victim, who got his car back, was recovering from his injuries.
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