Several Middle East nations, including the UAE, Bahrain, and Kuwait, have come under attack after the United States and Israel carried out strikes on Iran on February 28, triggering retaliation from Tehran. Explosions were heard across the Gulf region. Iran is targeting multiple countries that host tens of thousands of American troops stationed across the Middle East. The massive US military presence in the Middle East, including warships, fighter jets, and refuelling aircraft, lays the foundation for a major campaign against Iran.

Here’s a look at which countries are under attack and what Iran is targeting in each.

1. Bahrain
The tiny Gulf kingdom hosts an installation known as Naval Support Activity Bahrain, where the US Navy's Fifth Fleet and US Naval Forces Central Command headquarters are based. Bahrain's deep-water port can accommodate the largest US military vessels, such as aircraft carriers, and the US Navy has used the base in the country since 1948, when the facility was operated by Britain's Royal Navy. Several US ships have their home port in Bahrain, including anti-mine vessels and logistical support ships.

Bahrain said that the 5th Fleet's service centre was targeted by an Iranian missile strike on February 28.

2. Iraq
The United States has troops in Iraq's autonomous Kurdish region as part of the international coalition against the Islamic State group, but their mission is due to end by September under a deal between Washington and Baghdad. American forces have already completed their withdrawal from facilities in federal Iraq -- whose government is a close ally of Iran, but also a strategic partner of Washington -- under the same agreement.

AFP journalists reported explosions near the US consulate in Arbil -- the capital of Iraqi Kurdistan -- on February 28, while Iraq's powerful pro-Iran Kataeb Hezbollah group threatened attacks on American bases. Kurdish security forces later said the US-led coalition had intercepted multiple drones and missiles over Arbil.

3. Kuwait
Kuwait has several US bases, including Camp Arifjan, the location of the forward headquarters for the US Army component of CENTCOM. The US Army also has stocks of equipment and supplies in the country.

Ali al-Salem Air Base hosts the 386th Air Expeditionary Wing, which the military describes as the "primary airlift hub and gateway for delivering combat power to joint and coalition forces" in the region. Additionally, the United States has deployed drones, including MQ-9 Reapers to Kuwait.

Kuwait said its air defences engaged incoming missiles on February 28, while Italy's foreign minister said an Iranian attack caused "significant damage" to the runway of a Kuwaiti air base hosting Italian air force personnel.

4. Qatar
Al Udeid Air Base in Qatar includes the forward components of CENTCOM, as well as the command's air forces and special operations forces.

It also hosts rotating combat aircraft, and the 379th Air Expeditionary Wing, which the military says includes "airlift, aerial refueling intelligence, surveillance, and reconnaissance, and aeromedical evacuation assets."

Iran fired missiles at Al Udeid last June following US strikes targeting Iranian nuclear facilities, and the Gulf emirate said an Iranian missile attack targeted its territory on February 28.

5. Syria
The United States, for years, maintained troops in Syria as part of international efforts against the Islamic State group, which rose out of the country's civil war to overrun large parts of that country and neighbouring Iraq.

US forces are currently in the process of withdrawing from Syria, and three sources told AFP earlier this week that the American exit would be completed within a month. Syrian state media said four people were killed by an Iranian missile that hit the country's south on February 28.

6. United Arab Emirates
Al Dhafra Air Base in the United Arab Emirates hosts the US 380th Air Expeditionary Wing, a force that is composed of 10 squadrons of aircraft and also includes drones such as MQ-9 Reapers. Combat aircraft have rotated through Al Dhafra, which also hosts the US Air Force's hub for "advanced air warfare training."

The UAE said it had intercepted two rounds of Iranian missile attacks on February 28, with debris from the first wave killing a civilian in Abu Dhabi.