Several explosions have been heard over Qatar's capital Doha, a witness told Reuters.

Iran has fired missiles at a US base in Qatar. The missiles were visible over the capital Doha on Monday evening. All of the missiles were apparently shot down by US air defense systems.

“The White House and the US Department of Defense are aware of and closely monitoring potential threats to Al Udeid Air Base in Qatar,” a senior White House official told Axios.

Al Udeid Air Base in Qatar is the largest US military installation in the region, according to the newspaper.

A US official tells Reuters that there have been no recorded attacks on bases outside Qatar.

According to The New York Times, Iran gave Qatar a warning before the missiles were fired. It is not clear how far in advance the warning came.

Iran has previously warned of revenge after the United States attacked three Iranian nuclear facilities on Sunday night.

No deaths reported

Qatar condemns the Iranian attack on a US military base, writes the Reuters news agency.

No deaths have been reported following the attack on the military base, Qatar told the news agency.

Qatar says it reserves the right to respond after the Iranian attack. Iran's top security body, in turn, tells Qatar that the action poses no threat to our friendly and brotherly neighbor Qatar, according to Reuters.

The New York Times reports that Iran coordinated the attacks on the US military base in Qatar with Qatari officials, and gave advance warning that the attacks would come to minimize the number of casualties.

At the US Ain Al-Asad air base in Iraq, an air defense system has been activated in fear of a potential attack, military sources told Reuters.

Orders have been issued here to seek protection in bunkers, according to the news agency.

Iranian Tasnim writes that an operation called"Victory Announcement" has been launched against US bases in Iraq and Qatar, according to Reuters.

The main US base in Syria is also on full alert against possible attack from Iran or Iran-affiliated groups, a Syrian security source told Reuters.

Airspace closed in several places

Qatar's airspace was closed earlier on Monday. In a statement on Monday afternoon, Qatar's Foreign Ministry wrote that the decision to close the airspace was made in response to developments in the region.

Following the attacks on the military base in Doha, Bahrain has also decided to temporarily close its airspace.