The release of a man convicted in the murder of an officer with the Richmond (VA) Police Department in 1979 has been put on hold, and an investigation into the parole board's handling of his case has begun.

According to ABC News, Maureen Clements told reporters that she was notified Monday morning by the Virginia Parole Board that Vincent Martin—who has spent four decades in prison for her brother's on-duty death—would not be released as scheduled.

Patrolman Michael Connors was shot and killed after making a traffic stop of a car traveling the wrong way on a one-way street in November 1979.

Unbeknownst to Connors, the four occupants of the vehicle he had just stopped were had just committed an armed robbery of a convenience store.

At the traffic stop, several of the offenders opened fire on Connors, fatally wounding him.

All four suspects were sentenced to life in prison.

Martin presently remains at the Nottoway Correctional Center.