A man in his 50s was stabbed repeatedly on a downtown 1 train platform Wednesday morning, police said. View Full Caption DNAinfo/Trevor Kapp

CHELSEA — A man was repeatedly stabbed by a group of men on a downtown 1 train platform in Chelsea before stumbling out of the station and collapsing onto the sidewalk Wednesday morning, sources and witnesses said.

The straphanger — who identified himself to a good Samaritan as a 53-year-old named Kyle — had been in the 18th Street station at Seventh Avenue when he started arguing with a group of three or four men before one of them stabbed him multiple times in the torso about 5:30 a.m., sources said.

The group fled and the victim managed to climb out of the subway station and collapsed on Seventh Avenue as a tourist passed by on his way to a hotel, the visitor said.

"I pulled off his shirt and saw a couple stab wounds. He was stabbed twice in the stomach. His left arm was covered in blood. He was in fairly bad shape," said Dave Kucera, 39, who is visiting from Houston.

"He told me he was going to die. I said, 'You're going to be all right, Kyle,'" said Kucera, who then flagged down a cabdriver who dialed 911.

The victim was taken to Bellevue Hospital Center, but his condition was not immediately clear, officials said.

Police blocked off a section of Seventh Avenue north of 18th Street, where clothing, a black hat and a shopping bag from Mood Fabrics were scattered.

No arrests had been made as of Wednesday morning, police said.

Given the circumstances, investigators don't believe the attackers are linked to two recent fatal stabbing incidents in East New York, sources said. The suspect in Sunday's East New York elevator attack on two children and Friday's deadly stabbing of an 18-year-old young woman remains at large.

Southbound 1 trains were bypassing the station while police continue the investigation, according to the MTA.