Investigators believe speed was a factor in Green Line derailment

Updated:

BOSTON (MyFoxBoston.com) -- Investigators believe speed was a factor in a Green Line train derailment that sent 10 people to the hospital on Monday.

MBTA spokesperson Joe Pesaturo confirmed to FOX 25 on Tuesday morning that investigators believe speed was a contributing factor in the crash.

An official cause has not been released, though Pesaturo stated that "a thorough inspection of the track and signal systems found no defects nor anomalies."

Preliminary tests did not find any mechanical issues with the trolley, Pesaturo said, and investigators are continuing to "take a close look" at the action's of the train's driver.

Officials worked overnight to remove the derailed D branch train in time for the Tuesday morning commute. Normal service was restored just after 5 a.m., one day after the train derailed just west of Kenmore Station.

Boston EMS officials say 10 people were transported to the hospital after the derailment Monday afternoon. Most were treated for neck and back injuries.

The train's driver was treated and released.

MBTA officials told FOX 25 the first car of a two-car D train derailed and struck a wall. The train was bound for Riverside at the time of the derailment.

Transit Police said workers needed to move the derailed trolley, have structural engineers assess the wall, and restore power to the tracks.