The leader of a Hawaiian pro-sovereignty group that broke into a historic palace once home to royalty said he planned to chain himself to the throne but couldn't find it because he had never been in the palace before.

But palace officials said three locks, including those securing the throne room, were damaged. No artifacts were damaged or stolen, but the group broke into a barracks building and raised a flag on the flagpole, officials said.

Police arrested 23 people during the stunt, in which members of the Kingdom of Hawaii locked the gates to the Iolani Palace on Friday.

The leader, 67-year-old James Kimo Akahi of Haiku, claims he is the rightful king of the islands. He told reporters Saturday that he had never been in the palace before Friday and didn't know where the throne was kept.

The palace will remain closed indefinitely while curators assess damage. The state Department of Land and Natural Resources will decide when the palace can reopen, said Ruth Limtiaco, president of the Limtiaco Co., a public relations firm for the Friends of Iolani Palace.

During the takeover attempt, eight employees locked themselves in the palace and a nearby administrative building.

Several Native Hawaiian organizations have rival claims to sovereignty over the islands. Some supporters of sovereignty condemned Akahi's actions.

"That's atrocious, for him trying to sit on the throne at Iolani Palace," said Charles Kauluwehi Maxwell Sr., a priest and longtime Hawaiian activist. "James Akahi is not the king of Hawaii."

Another group calling itself the Hawaiian Kingdom Government occupied the palace grounds April 30 and has been getting permits to set up there each week since then. That group claims to be operating a functioning government from the grounds.

The 23 people arrested Friday face charges of criminal trespassing and burglary. State officers climbed over the fence a couple of hours after the takeover began.

Hawaiian activists have long used the site for protests against U.S. control of the islands. Legislation in the U.S. Senate would set up a Native Hawaiian governing entity similar to those of American Indians that could negotiate with state and federal governments over control of natural resources, lands and assets.

The ornate palace is operated as a museum of Hawaiian royalty. King Kalakaua built it in 1882, and it also served as the residence for his sister and successor, Queen Liliuokalani, the islands' last ruling monarch. Liliuokalani was later imprisoned in the palace after the monarchy fell.