BOSTON -- A New York city bar bouncer questioned in the death of a Boston graduate student in Manhattan has also been looked at in connection with three other brutal rapes that have taken place in the city.

NewsCenter 5's Gail Huff reported that Darryl Littlejohn, 41, of Jamaica, Queens has been interrogated in connection with the death of Immette St. Guillen, 24, whose raped and strangled nude body was found in Brooklyn Feb. 25 after she was last seen being escorted out of a SoHo bar by Littlejohn.

Littlejohn's van has now been impounded. It matches the description of a vehicle that was seen near where St. Guillen's body was discovered. Investigators have combed the van for hairs, fibers, blood and bodily fluids. A seat from the van was found inside Littlejohn's Queens home.

The bouncer is also being questioned about three other rapes in New York where in all cases the rapist posed as a federal agent and drove a van, according to The Boston Herald. Littlejohn told his employer he worked as a federal marshal and he often wore a jacket that said "Marshal" on the back, according to the Herald. He also displayed a badge around his neck, wore a bulletproof vest and carried a gun, the newspaper said.

In Littlejohn's Queens home, investigators reportedly recovered alcohol swabs and plastic ties. They have taken carpet samples, fibers and hair to see if any match samples taken from the floral blanket in which St. Guillen's body was wrapped.

Littlejohn is being held on parole violations at Riker's Island prison.