Washington has said it is checking reports that three US tourists were detained by Iranians while hiking along the northern Iraqi border.
The three are reported to have gone missing in Iraq’s autonomous Kurdish region which borders Iran.
Local Iraqi officials suggested the Americans might have been detained after straying into Iranian territory.
There was no immediate comment from Iran. The US said its embassy in Baghdad was investigating.
“We are using all available means to determine the facts in this case,” the state department said in a statement.
A senior security official in the Iraqi city of Suleymaniyeh, Qadr Hamajan, told Reuters news agency that the Americans were among a group of four hikers that had arrived there on Wednesday.
He said three of them set off the following day for the tourist resort of Ahmad Awa, about 150km (93 miles) to the east and near the Iranian border.
“They phoned their friend in Suleymaniyeh and told him ‘We are in trouble and are being held by soldiers who are not speaking Kurdish or Arabic’,” he said.
One unnamed border official was quoted as saying US helicopters and military vehicles had begun a search for the the missing tourists in the nearby city of Halabja.
The mountainous border region is popular for hiking. The Iraq-Iran border is not clearly marked in the area.
