Ed Mullins, the embattled former head of the New York City sergeants union will no longer have his shield or gun as the police department placed him on modified assignment on Wednesday, a day after federal agents raided the union’s office and his home.

Police Commissioner Dermot Shea said Wednesday that the NYPD‘s internal affairs bureau, which has been probing Mullins’ fiery tweets and other activity, was working with the FBI on the investigation that led to Tuesday’s searches.

“As a result of that work, you saw some of the investigative powers being exercised yesterday,” Shea was quoted by the Associated Press as saying.

Shea declined to comment further on the ongoing investigation.

An FBI spokesperson on Tuesday confirmed the raids were part of an active probe, but could not provide details.

Mullins resigned from the post of the president of the Sergeants Benevolent Association on Tuesday after being asked to do so by its executive board.

Mullins, a police sergeant who had been detached to the union full-time, was said to be mulling retirement from the police department rather than report to work for a modified assignment.

Mullins started as an officer in 1982 and was elected the union’s president in 2002. The union represents about 13,000 active and retired NYPD sergeants and controls a $264 million retirement fund.

NYPD personnel placed on modified assignment, often referred to as desk duty, are assigned to administrative, non-enforcement functions and must turn in their gun, shield, and department identification card, according to the NYPD’s patrol guide. They are paid the same as they would be on any other police assignment.

The union’s board, in a note to members, said the FBI investigation appeared to target Mullins and that it had no reason to believe any other union member was involved.

Mullins is in the middle of department disciplinary proceedings for tweeting NYPD paperwork last year regarding the arrest of Mayor Bill de Blasio’s daughter during protests over the Minneapolis police killing of George Floyd.

Mullins’ department trial began last month but was postponed after one of his lawyers suffered a medical emergency. It is set to resume on October 27.

(With AP inputs)