James Keivom/New York Daily News
Witnesses state Tomas Rivera was decapitated after he tied a rope around a pole (at left) across from 521 Longfellow Ave. and drove off in his vehicle on Monday in the Bronx. 
A man managed to behead himself in a spectacularly gruesome suicide in the Bronx Monday.
Tomas Rivera, 51, of upstate Port Jervis, tied a chain from his head to a pole, then hit the gas on his 2005 Honda CRV in Hunts Point, cops said.
He gunned it at 9:35 a.m., slamming into a parked vehicle on Longfellow Ave. near Randall Ave., police said. He was decapitated and died at the scene.
