By Shimon Prokupecz and Holly Yan CNN
(CNN) -- This wasn't the greeting Olympian James Blake is used to getting in New York during the U.S. Open.
The former tennis star and tournament darling says as many as five plainclothed police officers tackled and handcuffed him outside his Manhattan hotel Wednesday, according to the New York Daily News.
Blake, 35, was waiting for a car to pick him up and take him to the tennis tournament where he's doing corporate appearances, the paper said in an exclusive article.
According to the New York Police Department, Blake was detained during an ongoing investigation after he was misidentified by a witness.
Detectives from the Identity Theft Task Force were investigating the purchase of cell phones using fraudulent credit cards, two law enforcement sources told CNN.
Investigators organized a sting operation at the Hyatt Hotel, where phones were delivered to a male suspect who was later taken into custody, the law enforcement sources said.
That suspect identified two people in the lobby of the Hyatt to whom he had delivered cell phones that were purchased with a fraudulent credit card, they added.
Blake, who was once ranked No. 4 in the world, was one of the people placed in handcuffs but was let go shortly after a retired NYPD officer informed detectives that Blake was a tennis player.
"Once Blake was properly identified and found to have no connection to the investigation, he was released from police custody immediately," the NYPD said in a statement.
The second person identified by the suspect, who was not with Blake, was taken into custody, the sources added.
'It's blatantly unnecessary'
Blake suffered a cut to his left elbow and bruises to his left leg, according to the Daily News.
Blake, whose father was black and whose mother is white, said he doesn't understand why he was roughed up by the officers, who the Daily News reported are white.
"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," he told the News.
"I was just standing there. I wasn't running. It's not even close (to being OK). It's blatantly unnecessary,"
The 2008 Olympian later told CNN affiliate WABC he's looking forward to seeing what police make of the incident.
"It shouldn't happen, and it's something that you know we'll deal with, with the police, and we'll find out what they have to say internally," he told WABC.
New York Police Commissioner William J. Bratton directed the Internal Affairs bureau to investigate, the NYPD said in a statement.
"Subsequent to Internal Affairs investigators viewing surveillance video of the incident ... one officer has been placed on modified assignment," police said. "The investigation is ongoing."
According to his Facebook page, Blake "will most likely be commenting on this" Thursday.
CNN's Julia Talanova, Emily Smith and Rob Frehse contributed to this report.
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