A 19-year-old has been arrested in the Citi Bike slaying of a 16-year-old boy outside outside a swanky Soho hotel, police sources told The Post Friday.

The suspect is one of two alleged perps cops have been hunting after Mahki Brown was gunned down opposite the Dominick Hotel on Spring Street on May 7, sources said.

It isn’t clear if the arrested teen was the one who allegedly pulled the trigger, the sources added.

He was nabbed in Harlem early Friday morning by the US Marshals Service.

The victim was shot in the head and took two bullets to the leg in the brazen broad daylight attack last week.

Brown, who was an avid basketballer from Crown Heights, Brooklyn, was rushed to Bellevue Hospital where he was pronounced dead.

Police haven’t yet released a motive in the slaying, but law enforcement sources said initially it may have been school-related.