EAST BOSTON (CBS) — Four men in their early 20s were stabbed early Thursday morning.

A source told WBZ NewsRadio 1030’s Ben Parker that the attack happened when one group of men set upon another group of men outside a restaurant.

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The emergency call came in around 2 a.m. for the stabbings at the corner of Saratoga and Meridian Streets.

Three of the men were taken to local hospitals with serious injuries, while a fourth victim with non-life-threatening injuries went to a local walk-in clinic.

One of the victims, stabbed multiple times, made his way to a CVS pharmacy about a block away.

“I saw a gentleman walk in with red on his pants, and he turned around and I saw red on his hands,” said clerk Michael Rodriguez. “That’s when I asked him if he’s okay, if he’s in pain.”

Rodriguez said the man, who had six stab wounds in his back and chest, asked to be called a cab–but he instead called him an ambulance.

Rodriguez said the victim told him “a couple of guys” just “went on” him.

All of the victims’ injuries were believed to be non-life-threatening.

Boston Police spent hours taking photos and collecting evidence.

No arrests have yet been made.

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WBZ NewsRadio 1030’s Ben Parker reports