Eyewitnesses said they were demanding that Prime Minister Sheikh Nasser al-Mohammad al-Sabah step down.

Hundreds of people, including opposition lawmakers, have been protesting weekly outside parliament over alleged corruption.

The demonstrators broke open the gates to the parliament building and managed to enter the main chamber, where they sang the national anthem and then left a short time later.

Guardsmen did not intervene when they entered the parliament building, stormed after protesters' attempt to march on the prime minister's house were blocked.

Kuwait's parliament is one of the few elected bodies in the Gulf.