DETROIT -

Detroit police say a suspect has turned himself in for the stabbing of a 14-year-old boy on a city bus.

DeJon McGhee was stabbed in the chest last Wednesday evening after trying to break up an argument between two other riders near Dexter Avenue and Lawrence Street, police said. He remains in critical condition.

Witnesses said the other riders, two men, started talking about Martin Luther King Jr. and one of them claimed to have killed the civil rights leader.

When McGhee stepped in, his classmates said one of the men got upset.

"He called him names, he called him a (expletive). Then he told him that he killed MLK, something like that," said Precious Jones, one of the students who was on the bus. "Everybody kind of got upset on the bus."

Police said McGhee was defending himself when he punched the man in the nose. The man then took out a knife and stabbed him.

Police said they're not releasing additional information on the suspect until charges are issued.

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