Updated

A 15-year-old Pennsylvania boy is on the run and his 17-year-old brother reportedly remains in serious condition after a “Cain and Abel” slash attack, police said.

Upper Darby Police Superintendent  Michael Chitwood told the Philadelphia Daily News that the brothers were alone in their house on St. Laurence Road Saturday afternoon when they began fighting about money the older brother allegedly owed to his younger brother.

Chitwood said the younger teen at one point retrieved a butcher knife and began swinging it at his brother, saying he was going to kill him. The older boy put up his left arm in defense and almost lost his hand. He then put up his right arm and the 15-year-old caused a significant gash to that as well, Chitwood said.

The unidentified 17-year-old was taken to the Hospital of the University of Pennsylvania, where he remained in serious condition Sunday, police said. His brother, identified by police as Tyree Wilson, had not been apprehended as of Sunday afternoon. Chitwood said Wilson would be charged as an adult with aggravated assault and related offensives.

"He's lucky he didn't kill him. If the kid didn't defensively put the block up, he would have killed him," Chitwood told the newspaper. "The tragedy is that here's two brothers, and now one's almost dead and the other is wanted over something stupid."

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