U.N. experts have obtained satellite imagery of the site struck last month by Israeli warplanes and are analyzing it for signs that it might have been a secret nuclear facility, diplomats said Friday.

One of the diplomats, who is linked to the International Atomic Energy Agency — the U.N. nuclear watchdog looking at the images — said IAEA experts were looking at commercial images, disputing earlier suggestions that they had come from U.S. intelligence.

Separately, two diplomats said the images, acquired Thursday, did not at first examination appear to substantiate reports that the target was a nuclear installation, but emphasized that the photos were still under examination.

All of those who spoke to The Associated Press were briefed on the agency's receipt of the images but demanded anonymity because their information was confidential. Officials of the Vienna-based nuclear watchdog and the U.S. diplomatic mission to the IAEA had no comment.

Since the Sept. 6 bombing, news media have quoted unidentified U.S. officials as saying that the airstrike hit some sort of nuclear facility linked to North Korea, which is now in the process of dismantling its nuclear weapons program. On Friday, The Washington Post cited American officials as saying the site in Syria's eastern desert near the Euphrates River had characteristics of a small but substantial nuclear reactor similar to North Korea's facility.

The investigation by the IAEA is crucial because it is the first instance of an independent and respected organization looking at the evidence and trying to reach a conclusion as to what was hit.

Syria denies that it has an undeclared nuclear program. It has said the Israelis targeted an empty building, and the agency has said it has no evidence to the contrary.

The diplomats said that Vienna-based Syrian diplomats have met with senior IAEA representatives since the bombing, but have provided no substantive information that would indicate their country had nuclear secrets.

Syria has signed the Nuclear Nonproliferation Treaty and has allowed agency experts to inspect its only known nuclear facility — a small, 27-kilowatt reactor, according to diplomats linked to the IAEA.