Andrea Cabral’s chief of external relations will take over as Suffolk County sheriff, a source tells the Reporter. With Cabral signing on as Gov. Deval Patrick’s public safety secretary, Steven Tompkins will succeed her.

The State House News Service reported on Tuesday that Patrick will swear in Tompkins later today. A source with knowledge of the appointment confirmed the news to the Reporter.

Tompkins previously held communications jobs at Dimock Community Health Center, AT&T and the Federal Emergency Management Agency (FEMA).

He recently took a leave of absence from the sheriff's office in order to work on U.S. Sen. Elizabeth Warren’s 2012 campaign as a senior adviser. He is also listed as chair of Michelle Wu’s bid for a City Council At-Large seat.

Tompkins will fill out the rest of Cabral's term, with an election slated for 2014.

"As a dedicated public servant on the frontlines of crime prevention and reentry rehabilitation, Steven brings first-hand knowledge and passion to this critical position," Gov. Patrick said in a statement. "I am confident in his ability to serve Suffolk County in this role and I look forward to working with him to strengthen our re-entry programs and reduce youth violence."

Tompkins' biography on the Suffolk County sheriff’s website notes that under him, his department created two programs, including an inmate re-entry program focused on vocation skills and “The Choice Program,” in which corrections officers volunteer to work with middle and high school students. He also serves on the board of trustees for Roxbury Community College.

Tompkins is a graduate of Boston College and has a master’s degree from UMass Boston.

This post was updated at 12:28 pm with a statement from Gov. Patrick.