In this photo taken by a neighbour on Thursday, July 16, Harvard professor Henry Louis Gates Jr. is arrested at his home in the suburbs of Boston. (Associated Press)

A Cambridge, Mass., police sergeant who responded to a 911 call about a possible break-in at the home of black Harvard scholar Henry Louis Gates Jr. told dispatchers that Gates was being unco-operative and to "keep the cars coming."

Another voice can be heard in the background of the transmission, but it is unintelligible and unclear if it is Gates.

Cambridge police released recordings of police radio transmissions and of the 911 call Monday following more than a week of controversy over Gates's July 16 arrest on a disorderly conduct charge. The charge was dropped, but the encounter sparked a national debate about racial profiling.

Gates's supporters called his arrest by Sgt. James Crowley an outrageous act of racial profiling. Crowley's supporters say Gates was arrested because he was belligerent and that race was not a factor.

Interest in the case intensified when President Barack Obama said at a White House news conference last week that Cambridge police "acted stupidly" in arresting Gates. He later tried to quell the uproar about his comments and invited both Gates and Crowley to the White House for a beer, a meeting that could happen this week, according to the White House.

In the 911 recording released Monday, caller Lucia Whalen tells police she saw two men pressing on the door of a home, but says she is unsure whether the men live there or if they were trying to break in. She said she saw two suitcases on the porch.

"I don't know if they live there and they just had a hard time with their key. But I did notice they used their shoulder to try to barge in and they got in. I don't know if they had a key or not cause I couldn't see from my angle," Whalen said.

Whalen does not mention the race of the men she saw until pressed by a dispatcher to describe them. At that point, she said one of the men may have been Hispanic.

Whalen was vilified by some bloggers and others last week after it was incorrectly reported that she reported two black men trying to break into a home.

In the radio transmissions, Crowley tells a dispatcher he is at the home where the possible break-in was reported.

"I'm up with a gentleman, says he resides here, but was unco-operative, but keep the cars coming," Crowley said.

In his written police report, Crowley said Gates became angry when he told him he was investigating a report of a break-in, then yelled at him and called him a racist.