A man questioned by police in connection to an arson at one of Rep. Russ Carnahan's campaign offices used to work for his campaign, the Missouri Democrat said Wednesday.

The St. Louis Post-Dispatch reported Thursday that Carnahan said a man linked to the arson was fired just before the Aug. 17 incident in St. Louis. The man's name was recently published on a conservative blog.

Police have not filed charges against the 50-year-old man, who was arrested and questioned last week and police told the Post-Dispatch that the investigation is ongoing.

Carnahan is one of several lawmakers who have been subject to threats or acts of violence this year. A spate of threats were made against Democrats and Republicans following the vote on the healthcare reform law in March.

The congressman said at a press conference that, since the information became public, he felt the need to speak.

Carnahan said the individual was "paid for one week as a canvasser, was not doing his job, and was subsequently fired."

"It's our hope that someone is going to be prosecuted to the fullest extent of the law," Carnahan said.