The authorities in Kuwait say the two gunmen who killed an American marine and wounded another during a military exercise on the country's Failaka island were Kuwaitis engaged in a "terrorist incident".

The interior ministry named the attackers, who were shot dead in the firefight, as Anas Ahmad Ibrahim al-Kandari, 21, and Jassem Mubarak al-Hajri, 26.

The statement refrained from mentioning whether the men were Islamist elements linked to Osama Bin Laden's al-Qaeda network.

A second US marine was wounded in the attack.

The joint US-Kuwaiti exercise began on 24 September amid reports that US forces are preparing for possible military action against Iraq.

US officials insist the manoeuvres were planned long before the current confrontation over Iraq but the BBC's Nick Childs says tensions in the area are running high regardless.

Island sealed off

Pentagon spokesman David Lapan said the marines were taking part in a live fire exercise at about 1130 (0830 GMT) when they came under attack.

The Pentagon says the gunmen opened fire in one location, injuring the two marines, one of whom subsequently died.

The assailants then headed towards the unit's command post and opened fire again before being shot dead.

It seems there could have been a misunderstanding on which areas were sealed off for the exercise and these people entered the restricted area which was followed by shooting

Unnamed Kuwaiti official

The gunmen had AK-47 assault rifles, the Americans say.

A number of people were arrested after the incident and Failaka island has been sealed off as the US and Kuwait launch a joint investigation.

The BBC's Heba Saleh in Cairo says the US will be keen to know whether the attackers had any links with al-Qaeda.

US supporter

Kuwait is the strongest regional supporter of US plans to topple Iraqi leader Saddam Hussein - despite unanimous Arab League statements vigorously opposing unilateral military action.

There are already close to 10,000 fully equipped US troops in the country.

As many as 1,000 US troops are taking part in the Eager Mace annual exercises.