President Barack Obama said he spoke Friday with the white police officer involved in the controversial arrest of a black Harvard professor and said that he could have chosen his words more carefully when commenting on the incident. In a televised news conference Wednesday, Obama had decried the arrest of Henry Louis Gates Jr., one of the nation's leading black scholars, saying, 'The Cambridge (Mass.) police acted stupidly in arresting somebody when there was already proof that they were in their own home.' Friday, Obama showed up unexpectedly at the White House press room and said he had just gotten off the phone with Sgt. James Crowley, the officer who arrested Gates in the July 16 incident. 'My impression of him was that he was an outstanding police officer and a good man,' Obama said. 'And that was confirmed in my phone conversation. And I told him that.' The president continued: 'Because this is obviously ratcheting up and I helped to contribute to ratcheting it up, I want to make clear that in my choice of words I think I unfortunately gave an impression that I was maligning the Cambridge Police Department or Sgt. Crowley specifically. And I could have calibrated those words differently.' The incident involving Gates began when he and a driver tried to pry open the jammed door to his house near the Harvard Square neighborhood of Cambridge, just west of Boston. Someone called the police, who eventually arrested Gates for disorderly conduct, even after the professor proved that he lived at the house. The charges were later dropped. Crowley and Gates have given conflicting descriptions of the incident. Gates said he was singled out because he is black. Friday, Obama said, 'I continue to believe based on what I've heard that there was an overreaction in pulling Professor Gates of out his home to the station. I also continue to believe, based on what I've heard, that Professor Gates overreacted as well. 'My sense is that you've got two good people in a circumstance in which neither of them were able to resolve the incident in the way that it should have been resolved.' Some commentators and police officials across the country have charged that the president inserted himself inappropriately into a local issue. Obama said he rejected that assertion. 'The fact that this has become such a big issue, I think, is indicative of the fact that ... race is still a troubling aspect of our society,' he said. Before Obama's remarks, the head of a police labor union in Cambridge called on the president to apologize for saying that officers acted 'stupidly' in the arrest of Gates. 'I think the president should make an apology to all law enforcement personnel throughout the entire country who took offense to this,' Stephen Killion, the president of the Cambridge Police Patrol Officer's Association, said at a news conference in Cambridge. He was joined by Crowley and local and state union officials. Also Friday, the leader of another police union charged that Obama and Massachusetts Gov. Deval Patrick, who also criticized Gates' arrest, had gotten their facts wrong. Sgt. Dennis O'Connor, president of the Cambridge Police Superior Officers Association, pointed out that both Obama and Patrick qualified their statements by saying they did not have all the facts. If the president and governor didn't know the facts, O'Connor said, they should have refrained from comment. 'Instead both officials, both admitted friends of Professor Gates, proceeded to insult the handling of this case by the Cambridge Police Department,' he said. 