A 35-year-old man was fatally stabbed in the Bronx on Sunday, police said. Cops responding to a 911 call around 2:23 p.m. found Kadeem Grant with a stab wound to the chest inside a building on Grand Concourse near Anthony J Griffin Place in Mott Haven. Medics pronounced Grant dead at the scene. Police recovered a knife at the scene and have a person of interest in custody, cops said. An investigation was underway, police said.