DENVER -- FBI officials said Friday they have arrested a man who threatened to blow up Cincinnati's football stadium, airports in Denver and Cincinnati, Ohio River bridges, and other landmarks.

Frederick Purvis, 42, of Hamilton, Ohio, is accused of sending e-mails to two local media outlets and to the FBI threatening Paul Brown Stadium, the four bridges, the Cincinnati/Northern Kentucky International Airport and an Indiana casino, FBI spokesman Mike Brooks said.

FBI officials said Purvis was also charged with making e-mail threats to blow up the Denver airport. The other threats are cited in the federal complaint filed against him.

He is being held on federal felony charges of making a bomb threat, which carries a possible sentence of up to 10 years in prison, and of making a false terrorist threat, with a potential sentence of five years. FBI agents arrested Purvis on Thursday at a hotel in Erlanger, Ky., near the Cincinnati airport.

No explosives or bomb-making materials had been found, Brooks said. A federal magistrate on Friday ordered that Purvis remain in custody pending a psychiatric examination.

Purvis' father, also named Frederick, said his son has mental problems and has been on medication. He said he doesn't believe his son really planned to carry out any threats.

"I don't think he could build a bomb if he wanted to," the elder Purvis said. "I don't think there was any intent."

The FBI said in a statement that the Cincinnati and Covington, Ky., Joint Terrorism Task Forces began investigating after Cincinnati's WKRC-TV and WLW radio, as well as FBI headquarters, received e-mails warning that the four bridges, the stadium where the Cincinnati Bengals play, the Cincinnati airport and the Argosy casino would be "blown up" Nov. 14-16.

The e-mails used a fake name, the FBI said.

The investigation tied the e-mails to similar threats against the Denver airport sent in October to Denver television stations, the FBI said.