Pittsburgh Steelers halfback Rashard Mendenhall remained a target of sharp criticism by Twitter users on Tuesday after he posted a message questioning whether news that al Qaeda leader Osama bin Laden was killed should be cheered.

As spontaneous celebrations broke out in the hours after the nation learned bin Laden was shot dead by U.S. forces in Pakistan, Mendenhall used the social media site to denounce the response.

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, Mendenhall wrote in a message posted to the social media site on Monday.

Some Twitter users responded by asking if Mendenhall would have said the same thing when people celebrated Hitler's death, others said it was ignorant to give bin Laden the benefit of the doubt.

Mendenhall posted a series of about six Tweets, including one questioning whether the collapse of New York's Twin Towers was actually the result of al Qaeda hijackers flying planes into the buildings.

We'll never know what really happened. I just have a hard time believing a plane could take a skyscraper down demolition-style, said Mendenhall of the tragedy on September 11, 2001 that claimed 2,752 lives in New York City.

Steelers President Art Rooney II said in a message posted on the team's website that he had not spoken with Mendenhall, so it is hard to explain or even comprehend what he meant with his recent Twitter comments.

The entire Steelers' organization is very proud of the job our military personnel have done and we can only hope this leads to our troops coming home soon, Rooney said.

Mendenhall did not immediately respond to messages sent to him through Twitter.

(Reporting by Dan Lovering; Editing by Barbara Goldberg and Jerry Norton)