A Native Hawaiian sovereignty group took two boats from Maui to Kaho'olawe yesterday, landed on shore, set up a rock altar and planted a flag laying claim to the island.

The 18 members of the group calling itself the Reinstated Hawaiian Kingdom is challenging U.S. sovereignty over land taken during the 1893 overthrow of the Hawaiian monarchy, said Henry Noa, who identified himself as the group's "prime minister" by cell phone from the undeveloped island.

A few hours later, state officers arrested two of the members and issued citations to the rest for entering a restricted area, said Randy Awo, branch chief of the Department of Land and Natural Resources enforcement division. Their names and the exact charges against them were not immediately released.

"Our purpose is to reclaim our national land," Noa said. "We're staking our claim here. We're not terrorists. We're far from being terrorists. We're reasonable people."

Kaho'olawe is the smallest of the eight main Hawaiian Islands, and was established as a state reserve in 1993. It is seven miles southwest of Maui and covers about 44 square miles.

Access to Kaho'olawe is restricted because it is hazardous after decades of military training, said Sol Kaho'ohalahala, executive director of the Kaho'olawe Island Reserve Commission.

About 65 percent of the surface has been cleared of weapons and ordinance, and less than 10 percent of the surrounding waters are considered safe.

Ranchers once tended sheep and goats on the mostly lava-rock island, but it now has no permanent residents.

Members of the Reinstated Hawaiian Kingdom, which was formed in 1999 and claims 3,000 citizens, say their action on Kaho'olawe is justified by the 1993 Apology Resolution, in which Congress voted to apologize for the role the United States played in the overthrow of the Hawaiian Kingdom.

"They did not have the right to take it. That's what they admitted," said Dale Albertson, a Big Island district representative for the Reinstated Hawaiian Kingdom. "We're trying to remove it from future contamination and attempt to push forward the cleanup of the 'aina."

The Reinstated Hawaiian Kingdom is one of several Native Hawaiian groups seeking various ways to restore Native Hawaiian rights and rule in the Islands.

The state Office of Hawaiian Affairs is moving ahead with its vision for a Hawaiian government within the framework of the United States, according to OHA Administrator Clyde Namu'o.

"It's too bad that people are trespassing," Namu'o said. "The United States was apologetic, but I'm not sure you can say that's the basis for reclaiming land."

The Navy concluded its 10-year cleanup operations on Kaho'olawe in 2003, although officials say much ordnance remains buried, rests on the land surface or lies beneath waters offshore.

The Kaho'olawe Island Reserve Commission prohibits access except for Native Hawaiian cultural purposes, environmental restoration, education and rehabilitation of the habitat.

Commission officials say they prepare for such access ahead of time, informing groups about the risks involved.

Noa said his group maintains that the Hawai'i government is the one trespassing on Kaho'olawe, and it plans to continue efforts to reclaim its land and national identity.