The U.S. military launched attacks on Iran's Qeshm Island as part of a defensive operation, according to U.S. officials

The United States military carried out limited strikes on Iran’s Qeshm Island on Monday, in an operation described by U.S. officials as defensive and intended to protect U.S. assets in the region. Three officials told CNN that the attack was launched after Iran allegedly used surface-to-air missiles against a U.S. aircraft.

The operation does not appear to have the scope of a major offensive, and the U.S. administration reportedly kept it deliberately low-profile. The Wall Street Journal reported that similar strikes had previously taken place in secret. Iranian news agency Fars reported that several explosions were heard on Qeshm and in nearby areas, including Bandar Abbas and Hengam Island.

Qeshm is located approximately 22 kilometers from Bandar Abbas and occupies a strategic position at the entrance to the Strait of Hormuz, through which around 20 million barrels of oil per day passed before the war. The attack comes as Donald Trump maintains that a deal with Tehran is possible, but warns that the U.S. could strike the underground Pickaxe Mountain nuclear facility. Iran is threatening a response without geographical limits.