CHICAGO (CBS) — A 50-year-old man accused of attacking his longtime friend and neighbor with a chainsaw was taken into custody overnight.

WBBM Newsradio’s Mike Krauser reports charges were pending against the suspect early Thursday, following his arrest late Wednesday night.

The man’s neighbor, 55-year-old Preston Smith, underwent surgery Wednesday to repair a gash to his left hand. Smith and his friend of 30 years had been drinking in the neighbor’s back yard near 103rd and Carpenter streets around 1 a.m. Wednesday, when they began arguing.

Something happened, or something was said that quickly turned the conversation sour.

“They were supposed to be best of friends,” said Preston’s mother, Mildred Smith. “I can’t fathom what has happened.”

Mildred said her son and his friend argued, and Preston got into his vehicle to leave, but his friend didn’t back down.

“He said the next thing he knew, he came out of his back yard with the chainsaw,” she said. “He was sitting in his car with window down, and he started attacking him.”

Mildred said her son stepped out of the car to reason with his friend.

“That’s when he started slashing at him, and he threw up his hands,” she said. “The left hand is wrapped, all the way down to the very tip of his fingers.”

The fingers on Preston’s left hand were badly cut, but not completely severed. The father of two was scheduled to undergo surgery Wednesday afternoon at Advocate Christ Medical Center in Oak Lawn.

Mildred said she doesn’t hate her son’s friend for what he did.

“I think it just got out of hand … where alcohol, or drugs, or whatever’s involved; it’s not your mind anymore,” she said.

The suspect disappeared after allegedly attacking Preston with the chainsaw, but was taken into custody late Wednesday night.