The House Ethics Committee extended its probe of Rep. Michele Bachmann, committee leaders announced Friday.

Committee chairman Rep. Mike Conaway, R-Texas, and ranking Democrat Rep. Linda Sanchez, D-Calif., made a joint decision to further investigate a matter involving the Minnesota Republican though they did not specify the subject of the probe.

It is likely to stem from a complaint filed by a former staffer on Bachmann‚Äôs presidential campaign who claimed she illegally used funds to pay staff. A short statement indicated only that an incident was brought to the committee for review by the non-partisan Office of Congressional Ethics on June 13.

Bachmann, who announced plans to retire from her House seat, has also been in the news recently after firing a congressional staffer who was allegedly caught stealing from her office.

Other statements released Friday indicated that incidents involving Reps. Tim Bishop, D-N.Y., Peter Roskam, R-Ill., and John Tierney, D-Mass, would also receive further committee review.

The committee is likely to address the matters at its Sept. 11 meeting.