WASHINGTON — US officials confirmed Turkish press reports on Friday that two ­Tunisian men had been detained in Turkey in connection with the killing of Ambassador J. Christopher Stevens and three other Americans in the attack on a US diplomatic post in Libya on Sept. 11.

But the officials said they were awaiting more information from the Turkish authorities, and it remained unclear whether the two are suspects or witnesses in the violent attack in Benghazi, which fell on the 11th anniversary of the 2001 terrorist attacks.

Kanal D, a private Turkish television network, said the two were stopped at Ataturk Airport in Istanbul Wednesday as they tried to enter the country using false passports.

Another report, in Sabah, a Turkish newspaper, said that immigration officials had matched the names of the men, who were said to be in their mid-30s, to a list of possible suspects that US intelligence agencies had given to security services in the region.

Turkish police officials declined to comment.

A State Department spokesman, Mark C. Toner, said Friday that US officials “have been in contact with the Turkish government on this issue,” but referred more detailed inquiries to the Federal Bureau of Investigation. Asked about the detained Tunisians, an FBI spokesman, Paul E. Bresson, said officials were not “ready to discuss at this point or in any way characterize what their involvement may or may not have been.”

President Obama has repeatedly pledged to “bring to justice” those responsible for the deaths of Stevens, Sean Smith, Tyrone S. Woods, and Glen A. Doherty.