The four men -- two navy colonels, a captain and a lieutenant commander -- admitted they had been tasked by Iran's ideological army with "infiltrating" Bubiyan Island, Kuwait's interior ministry said in a statement published by state news agency Kuna.

Iran's foreign ministry denied the allegations, calling them "absolutely baseless", and said the four officers had entered Kuwaiti waters by mistake "due to disruption in the navigation system".

The island is Kuwait's largest and is located near the Iranian coast. The group attempted to enter on May 1 "aboard a fishing boat specially chartered to carry out hostile actions against Kuwait", the ministry said.

A Kuwaiti serviceman was wounded during an exchange of fire with Kuwaiti forces on the island, and two of the Revolutionary Guard members managed to escape, it added.

The Kuwaiti foreign ministry later said it had summoned the Iranian ambassador, Mohammad Toutounji, to hand him "a letter of protest following the infiltration on the island of Bubiyan of an armed group belonging to the Revolutionary Guards and their involvement in clashes with the Kuwaiti Armed Forces".

The ministry denounced it as a "hostile act" and a "flagrant attack" on Kuwait's sovereignty, adding that it reserves "the right to self-defence".

It marks the fourth time that the ambassador has been summoned since the Middle East war began and Iran launched its retaliation against Gulf countries in late February.

In its statement, Iran's foreign ministry accused Kuwait of "politically and propagandistically exploiting the case".

It called for its embassy in Kuwait to have "access as soon as possible" to the detained officers.

Since the Middle East war began, Kuwaiti authorities have sought to crack down on individuals and groups with alleged links to Iran.

And in mid-April, 24 people were arrested in the country for financing "terrorist" entities, according to the interior ministry, while a security source said five former lawmakers were among those arrested.