Internal affairs detectives are investigating claims by former tennis professional James Blake that he was thrown to the ground and then handcuffed while mistakenly being arrested Wednesday at a Manhattan hotel, police said.

Blake, 35, who is biracial, told the New York Daily News he wasn't sure if he was arrested because of his race but said the officer who put him in handcuffs inappropriately used force.

"To me it's as simple as unnecessary police force, no matter what my race is," he told the newspaper. "In my mind there's probably a race factor involved, but no matter what, there's no reason for anybody to do that to anybody."

The agent who represented Blake when he was a professional tennis player, Carlos Fleming, did not immediately respond to a request for comment from The Associated Press.

Stephen Davis, the New York Police Department's top spokesman, said a cooperating witness misidentified Blake to detectives investigating fraudulently purchased cellphones as one of two people he recognized as being involved with the scheme.

"Once Blake was properly identified and found to have no connection to the investigation, he was released from police custody immediately," Davis said in a statement. "In regards to the alleged improper use of force, the police commissioner directed the internal affairs bureau to investigate."

Speaking on the NY1 cable television news station, Police Commissioner Bill Bratton said Blake "has a right to be upset." Bratton vowed to aggressively address Blake's allegations.

"It's very disturbing," Bratton said. "The nature of what he described is not what we do; it's not what we're supposed to do."

Officers arrested a suspect in the cellphone scam at the Grand Hyatt New York during a controlled buy earlier Wednesday, police said. It was after that buy that a deliveryman with the cellphone company pointed out Blake and another man in the hotel lobby as having purchased cellphones the day before, officers said.

The second man, who Bratton said was standing next to Blake, was taken into custody. A security guard at the hotel, himself a former member of the NYPD, recognized Blake, prompting the arresting officers to confirm his true identity.

Bratton said internal affairs detectives were sent to the hotel and have already identified "a number of witnesses." He says investigators are also looking to obtain surveillance video from the hotel that may have captured the arrest.

Blake's last tournament as a professional was the 2013 U.S. Open, where he lost in the first round of singles and doubles. He was ranked as high as No. 4 in the world and reached three Grand Slam quarterfinals, including at the U.S. Open in 2005 and 2006.

Blake was born in Yonkers and went to high school in Connecticut, then attended Harvard before turning pro in 1999.