FILE – In this July 26, 2017 file photo, Illinois Speaker of the House Michael Madigan, D-Chicago, speaks at a news conference at the state Capitol. (Justin Fowler/The State Journal-Register via AP, File)

CHICAGO, Ill. (AP) — A published newspaper report says the longest-serving state House speaker in modern U.S. history is a subject of inquiries in an ongoing federal corruption investigation that has already entangled several top Illinois Democrats.

Four unnamed sources interviewed by investigators told the Chicago Tribune that FBI agents and prosecutors asked about Illinois House Speaker Michael Madigan’s ties to ComEd lobbyists, contracts the utility had with Madigan associates and government jobs those close to Madigan have landed. Madigan hasn’t been accused of wrongdoing.

Madigan spokesman Steve Brown did not return a message from The Associated Press seeking comment Thursday.