CHICAGO — Federal authorities in Chicago have arrested Illinois Gov. Rod Blagojevich based on allegations that he attempted to benefit financially from his position to appoint Barack Obama's Senate replacement.

U.S. Attorney's office spokesman Randall Samborn says both Blagojevich and his chief of staff John Harris were arrested Tuesday.

Authorities also accused Blagojevich of threatening to withhold state assistance to the Tribune Co. in connection with the sale of Wrigley Field to induce the firing of editorial board members who have been critical of the governor.

A federal official, speaking on condition of anonymity, told The Associated Press that the allegations include that the governor took money from at least one individual in connection with naming a successor for the U.S. Senate seat that was vacated by Obama. The official declined to be named publicly because the investigation was still under way.

Blagojevich is charged with conspiracy to commit mail and wire fraud and solicitation of bribery.

Federal agents are in Blagojevich's office in the Thompson Center in downtown Chicago.

The governor has repeatedly denied any wrongdoing.