ALBANY, N.Y. • Former Weather Underground radical David Gilbert has been granted parole after 40 years behind bars for his role in a deadly 1981 Brink’s robbery that was a violent echo of left-wing extremism born in the 1960s, the state corrections department said Tuesday.

Gilbert, 76, has been imprisoned since shortly after the infamously botched armored car robbery in which a guard and two police officers were killed. He became eligible for parole only after his 75 years-to-life sentence was shortened by Gov. Andrew Cuomo in August, hours before he left office.

Gilbert appeared before the state parole board Oct. 19 and was subsequently granted parole, Thomas Mailey, a spokesperson for the New York state corrections department, said Tuesday.

He will be able to leave Shawangunk Correctional Facility in the Hudson Valley next month.

Supporters — including his son, San Francisco District Attorney Chesa Boudin — lobbied to have Gilbert join other defendants in the case who have been released from prison.