RALEIGH, N.C. -- Pittsburgh Steelers running back Rashard Mendenhall is suing the parent company of the Champion sports apparel maker, calling the decision to drop his endorsement deal over his tweets about the death of Osama bin Laden and the Sept. 11 terrorist attacks a breach of contract.

Mendenhall's lawyers filed suit Monday in U.S. District Court in North Carolina, seeking roughly $1 million in damages from Hanesbrands, Inc., the Winston-Salem-based corporate parent of Champion.

The complaint says Champion's decision to end its endorsement deal with Mendenhall in May, days after he questioned the public celebration of bin Laden's death, violates a contract extension the two parties signed in 2010, worth more than $1 million. Mendenhall first signed a deal to endorse Champion products when he entered the league in 2008.

"For Rashard, this really is not about the money. This is about whether he can express his opinion," said Steven Thompson, a Chicago-based attorney representing Mendenhall.

A spokesman for Hanesbrands did not return a call seeking comment by early Tuesday afternoon.

Shortly after bin Laden was killed by a team of Navy SEALs, Mendenhall tweeted, in response to scenes of euphoria around the U.S., "What kind of person celebrates death? It's amazing how people can HATE a man they have never even heard speak. We've only heard one side..."

He also tweeted on the Sept. 11 attacks: "We'll never know what really happened. I just have a hard time believing a plane could take a skyscraper down demolition style."