A 25-year-old man driving an unregistered dirt bike was killed Friday when he ran into a car in The Bronx — and his runaway bike ­injured two pedestrians, cops said.

The biker was riding south on Third Avenue in Belmont when he passed a Toyota sedan as it turned left onto East 188th Street at about 3 p.m. The sedan collided with the dirt bike, throwing the driver into the air as his bike flew into a 55-year-old man and an 85-year-old woman, cops said.

Both pedestrians were injured and hospitalized in stable condition while the unidentified driver was pronounced dead.