Adding to the controversy surrounding the capture of US sailors by the Iranian military last week is the fact that Iran kept the SIM cards of two US satellite phones. All other items were returned. CENTCOM has published a report that detailed the situation.

WASHINGTON — Iranian soldiers removed two SIM cards from two handheld satellite phones but otherwise returned all weapons, ammunition and equipment when they released 10 U.S. sailors and their two boats last week, the Pentagon said Monday.

The first public report from U.S. Central Command into the incident provided that and other new details but did not answer the key question of why the U.S. Navy crews deviated from their course in the Persian Gulf and entered Iranian waters.

The crew and the two boats were detained overnight by Iran’s military on Farsi Island and were released unharmed Wednesday morning after about 15 hours in custody.

Central Command, which oversees U.S. military operations in the Middle East, said the two Navy crews departed Kuwait Tuesday shortly after noon local time en route to Bahrain, more than 300 miles away.

They were supposed to follow a course that would keep them in international waters. They were scheduled to refuel at a rendezvous with the Monomoy, a Coast Guard cutter, at about 5 p.m.

But the two boats veered off course into Iranian waters.

“The command investigation will determine what caused the change in course and why the (boats) entered into Iranian territorial waters in the vicinity of Farsi Island,” the report said.

The crews then stopped to try to fix a mechanical problem in one boat’s diesel engine.

“This stop occurred in Iranian territorial waters, although it’s not clear the crew was aware of their exact location,” the report said.

At about 5:10 p.m., one of the boats apparently sent a brief radio report that Iranian boats were approaching. A second message was garbled. All communications were cut off by 5:45 p.m., the report said.

U.S. commanders launched search and rescue aircraft from the Harry S. Truman, an aircraft carrier then 40 miles southeast of Farsi Island. French and British warships in the region also participated.

The Navy attempted to contact Iranian military units by broadcasting details of the search and rescue effort over marine radio, and notified Iranian coast guard units via telephone, the report said.