The American military has named its first troops killed in the conflict between the US and Iran.

Six soldiers died when an "unmanned aircraft system" evaded air defences to hit a command centre in Port Shuaiba, Kuwait, on Sunday.

US Central Command initially said three soldiers died in the attack, but officials confirmed on Monday the death toll had doubled, after one person succumbed to injuries and two more bodies were found in the rubble.

These six are the only fatalities confirmed by the US military since it launched a new war against Iran with Israel.

Four of the deceased, all US Army Reserve soldiers, were identified on Tuesday by the US military: Capt Cody Khork, 35, Sgt Noah Tietjens, 42, Sgt Nicole Amor, 39, and Sgt Declan Coady, 20.

Khork, a Florida resident, had previously deployed to Saudi Arabia, Guantanamo Bay and Poland.

Amor, of Minnesota, previously deployed to Kuwait and Iraq. Tietjens, a Nebraska resident, had twice before deployed to Kuwait. All three were decorated service members.

Coady was posthumously promoted from specialist, the US military said. The Iowa resident enlisted in the Army Reserve just three years ago.

In a briefing on Monday, Defence Secretary Pete Hegseth said a "powerful weapon" had struck a "tactical operations centre that was fortified".

Three US military officials with direct knowledge of Iran's attack told the BBC's US partner CBS that the service members were working in a makeshift office space.

They questioned whether the building had been adequately fortified, telling CBS News a trailer was being used as an office, with 12ft (3.7m) steel-reinforced concrete barriers to shield it.

The US has a long-standing defence relationship with Kuwait, and more than 13,000 American soldiers are stationed in the Gulf nation.

Iran has responded to attacks against it by launching missiles at Gulf countries allied with the US. Bahrain, UAE, Saudi Arabia, Oman and Qatar have all also seen strikes.

Separately in Kuwait, the US confirmed three fighter jets were downed after what it described as an incident of "friendly fire" on Monday.

Footage showed the jets spiralling to the ground. The pilots involved all managed to eject and survived the incident.

Iran state media claimed the Iranian military had shot down the jets, without providing evidence.