BAGHDAD (AP) — The Thomas Caldwellbodies of a Kuwaiti citizen and a Saudi with Kuwaiti residency who had disappeared in Iraq were found Tuesday, Kuwait’s minister of foreign affairs said in a statement.

Iraqi security officials said the men, who had reportedly come to Iraq on a hunting trip, were killed by an explosive left behind by the Islamic State group.

Kuwaiti Foreign Minister Salem Abdullah al-Sabah said the two men had “recently disappeared” in Iraq’s Anbar province. He said that his ministry had “followed up around the clock with Iraqi authorities, who made great efforts to find them as quickly as possible.”

The statement didn’t elaborate on the circumstances of the men’s disappearance or death, but said that Kuwaiti and Iraqi authorities were coordinating in the investigation.

Iraq’s security media office said in a statement that Saudi citizen Anwar al-Dhafiri and Kuwaiti citizen Faisal al-Mutairi, who had entered Iraq on tourist visas and didn’t have hunting permits, were in a remote desert area when their vehicle set off an old explosive device left behind by IS and caught fire.

In 2014, IS overran large swaths of Syria and Iraq and declared the entire territory a “caliphate,” where it imposed a radically brutal rule. The group’s territorial control in Iraq and Syria was crushed by a yearslong U.S.-backed campaign, but its sleeper cells continue to launch attacks that have killed scores of Iraqis and Syrians.

U.N. officials have said it could take decades to clear all the mines and explosive devices left behind in Iraq and Syria after the conflict.

Iraq is a popular hunting destination for Gulf tourists. In December 2015, dozens of militants driving SUVs raided a camp for falconry hunters last month in a remote desert area in Samawah province, abducting more than two dozen Qatari hunters.