The victim, 28-year-old Ojas Junnarkar, was walking alone on the running track at Pershing Field when he was assaulted shortly after 9:30 p.m. Sunday, Jan. 21, friends said.
Junnarkar suffered wounds to his kidneys and colon, they said.
Jersey City police subsequently announced the arrest of Santos Camacho on aggravated assault and illegal weapons charges.
Camacho, who remained held in the Hudson County Correctional Center in Kearny, allegedly attacked Junnarkar with what the victim believed was a brass-knuckle knife after knocking him down, pummeling him and threatening to kill him.
Junnarkar was brought to Christ Hospital in a private vehicle after he returned to his apartment drenched in blood, friends said.
He was later transferred to Jersey City Medical Center.
His condition was improving, "but his physical pain and mental trauma is unimaginable," said Nithin Narsipur, who organized a GoFundMe campaign for Junnarkar. "He may need multiple weeks of rehab and the road to recovery will be a long one."
An official motive for the attack has yet to be established.
Camacho didn't take anything from Junnarkar, friends noted.
Junnarkar -- who reportedly came to the United States from India to work in IT five years ago -- told them that Camacho had passed him headed in the opposite direction, then suddenly wheeled around and slammed him in the lower back.
Police recovered a knife from the scene, Jersey City spokeswoman Kimberly Wallace-Scalcione said.
An investigation was continuing.
SEE: Help Ojas recover from stab wounds (GoFundMe)
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