BOSTON -- A Massachusetts Bay Transportation Authority bus struck and killed a bicyclist on Wednesday evening.

MBTA spokesman Joe Pesaturo said the accident involved a Route 39 bus and the bicyclist near the intersection of South Huntington and Huntington avenues at about 6 p.m.

The bicyclist was identified as a 23-year-old man, who was trying to pry his bicycle wheels from the trolley tracks. T police said the bicyclist was struck after he made contact with the rear of the bus.

"As a result, the male was pronounced dead not long after arriving at the hospital," Boston police Superintendent Rafael Ruiz said.

Several witnesses said the victim's bike got stuck on the Green Line train tracks moments before the bus hit him. They said the bicyclist didn't have a chance.

"I saw this person get stuck on the tracks. (He) didn't have a lot of time to react." - Joe Leary

"I was coming off the 66 bus, coming down here, and I saw this person get stuck on the tracks. (He) didn't have a lot of time to react," said Joe Leary, a witness.

Witnesses said the man was struggling to free his bike when the bus came around the corner heading east. The driver had about 150 feet to react.

Pesaturo said the bus operator is 29 years old with two years of service and a good driving record with no violations for safety or driving.

"It was too late for the driver or him," Leary said. "(I) see a lot of close calls, but nothing like this."

Police shut down Huntington Avenue and streets in the immediate area as accident reconstruction teams investigated. The road re-opened at about 10:20 p.m., at which time, Green Line E train service would resume. The line had been terminated at the Brigham Circle station and buses shuttled commuters between the Brigham Circle and Heath Street stations.

Other bicyclists passing the scene said they will think twice from now on.

"(To) see this accident, I think I have big enough tires, but will think twice before going over tracks," said Lee Stepien, of Jamaica Plain.

While the accident remains under investigation, residents and bicyclists said the incident provides another strong argument for why the city of Boston should make a better effort to install bike lanes.