WASHINGTON — Unhappy with the Pentagon’s oversight of its private contractors in Iraq, Defense Secretary Gates has dispatched a fact-finding team to probe further into the problem.

A spokesman for Mr. Gates, Geoff Morrell, said today that the Pentagon chief began asking questions about the military’s relationship with these contractors after 11 Iraqis were killed September 16 in a shooting involving Blackwater contractors protecting an American diplomatic convoy in Baghdad.

The Blackwater employees in that case were working for the State Department.

“He’s asked some early questions, he’s received some early answers,” Morrell said. “Those answers, at least when it comes to the oversight component, have not been satisfactory.”

Mr. Morrell would not elaborate on what Mr. Gates found unsatisfactory.

“He has some real concerns about oversight of contractors in Iraq and he is looking for ways to sort of make sure we do a better job on that front,” Mr. Morrell told reporters at the Pentagon.

As a result, Mr. Gates sent a five-person team to Iraq on Sunday to “talk to all the key players,” including the top two American commanders there, General David Petraeus and Lieutenant General Ray Odierno, and obtain additional details for Mr. Gates by the end of this week, the press secretary said.

Also, Deputy Defense Secretary Gordon England issued a memorandum to commanders yesterday spelling out what authority they already have to ensure that private contractors comply with American rules, Mr. Morrell said.

The memo tells the commanders that they have the authority to ensure that all security contractors are authorized and trained to carry weapons and that none has unauthorized weapons or ammunition, he added.

There are about 7,300 private contractors working for the Pentagon in Iraq, Mr. Morrell said, adding that about 5,000 of them are securing fixed sites of importance to the American military or the Iraqi government.