Burris of chief of staff leaves

Embattled U.S. Sen. Roland Burris's chief of staff is leaving the job.

Interim Chief of Staff Darrel Thompson is going back to work as a senior adviser to Senate Majority Leader Harry Reid.

Thompson said in a Friday statement he was temporarily detailed three weeks ago to serve as Burris' chief of staff and the role ended Friday.

It was not immediately clear who would replace Thompson.

Burris is under pressure to resign from the Senate for not disclosing contacts with advisers to former Gov. Rod Blagojevich. Blagojevich appointed Burris to the seat before being impeached and ousted over corruption allegations.

The White House has said Burris should think about his future and Illinois Gov. Pat Quinn has joined a growing chorus of people calling on Burris to quit.