DETROIT - The FBI yesterday searched the office of a city contractor who is an ally of former Mayor Kwame Kilpatrick.

Agents removed boxes from Ferguson Enterprises.

The FBI was working with investigators from the Environmental Protection Agency and the Department of Housing and Urban Development.

An affidavit supporting the search was sealed in federal court, "so we cannot discuss the case," FBI spokesman Sandra Berchtold said.

She didn't know if Bobby Ferguson or anyone else was at the office when agents arrived in the morning.

"If nobody's there we generally try to get a locksmith," Ms. Berchtold said.

Messages seeking comment were left at Ferguson Enterprises and with Mr. Ferguson's lawyer.

Mr. Ferguson's company has done demolition work and other jobs for the city. He and Detroit officials defended his contracts last year after the Detroit Free Press said he had won deals worth millions while getting secret guidance from Kilpatrick's top aide.

Mr. Ferguson has a cousin who is married to Kilpatrick's sister, Ayanna.

The FBI, with the help of a grand jury, is investigating corruption in Detroit city government.

Two former directors of Cobo Center who took bribes from another contractor have pleaded guilty to financial crimes.

Kilpatrick left office in September after his convictions for obstruction of justice in a civil lawsuit and the assault of sheriff's officers.

He began serving a 120-day sentence on Oct. 28.

First Published January 16, 2009, 12:04 p.m.