A man in his 20s from the Fitchburg area went to a State Police barracks this morning and said he had personal information about yesterday's hit-and-run of a state trooper.
The man has not been charged, but is being questioned, police said.
State Police Colonel Marian McGovern would not say whether the man was the driver of the black sedan that hit and seriously injured Trooper Joseph Drane as he worked a detail in a South Boston tunnel. However she did say he implicated himself.
Troopers were also looking for the drivers of two other cars that were cut off by the suspected hit-and-run car.
It was not clear if the man who went to the barracks was a passenger in the car or how exactly he is related to the incident.
McGovern said police are still looking for the vehicle in the Boston and Fitchburg areas.