JERUSALEM -- Israel's military on Tuesday ordered 15 Palestinian detainees expelled from the West Bank to the Gaza Strip, an action human rights groups denounced as a violation of international law.

The new Palestinian prime minister, meanwhile, sparred in public with Yasser Arafat -- a sign the rift between the two is deepening, as Israeli troops invaded a Palestinian refugee camp on the Gaza-Egypt border, looking for arms-smuggling tunnels.

The military said expulsion orders for 15 Palestinians held in Israeli custody were the only way to be sure the detainees would not return to terror activity. The military said most are members of the Hamas and Islamic Jihad militant groups.

None participated directly in attacks on Israelis or had "blood on their hands," an army statement said, but all were accomplices to violence.

The 15 were being held in military lockups without trial, in what is called administrative detention. They cannot be tried, the army said, without exposing sensitive intelligence sources. The detainees have already been moved to an army jail near the Gaza Strip and have two days to appeal.

Arafat said late Tuesday that he has sent messages of protest to the United Nations and the Islamic Conference. He said the expulsions "are part of the conspiracy," without elaborating. He was speaking after meeting the Norwegian foreign minister.

'Dangerous step'

Palestinian Cabinet minister Saeb Erekat said the army order "is a very dangerous step" and should be condemned by the international community.

In the past, the military has said expulsion acts as a deterrent, but Israel's Supreme Court, in a 2002 ruling, severely limited the practice to only those directly involved in violence.

Expulsion is an especially sensitive issue for Palestinians, many of whom were made refugees as they fled or were forced out of what is now Israel during Mideast wars. For most Palestinians, exile or any removal from their land and families is worse than prison.

The military has issued such expulsion orders only twice before, and three people accused of being accomplices to suicide bombings were sent to Gaza. One was said to have sewn belts to be fitted with explosives and strapped to suicide bombers' bodies. At first, the military wanted to expel 21 relatives of militants, but the Israeli court prevented that.

Even with the court's limitations, human rights groups say the practice violates international law.

Meanwhile, a dispute deepened between Arafat and his prime minister, Ahmed Qureia, who have haggled over the formation of a new Cabinet and especially over who should take up the powerful post of interior minister.

On Monday, Arafat appointed a top member of his Fatah party, Hakam Balawi, to be acting interior minister. In a show of defiance, Qureia, who had supported another choice for the post, told reporters Tuesday Balawi did not have the job.

Further, Qureia said the powers and responsibilities of the Interior Ministry would be taken over by the Palestinian national security council for now.

Last week, Qureia lost his battle to get parliamentary approval for the Cabinet, formed by Arafat decree. Qureia has threatened to quit once the term of his temporary government expires in about three weeks. Similar wrangling led to the resignation last month of the previous prime minister, Mahmoud Abbas.

The United States and Israel have been pushing for a prime minister to head a government as an alternative leader to Arafat, whom both nations accuse of backing terrorism. The goal is to work for implementation of the "road map" peace plan, but with the U.S.-Israeli boycott of Arafat, a stable Palestinian government is needed before any steps can be taken.

Violence continued Tuesday. In a raid on the Rafah refugee camp in southern Gaza before dawn, army bulldozers destroyed four homes, while troops took over several buildings and snipers set up rooftop positions. Six Palestinians were wounded in gun battles.

Col. Pinchas Zuaretz, commander of Israeli forces in the southern Gaza Strip, said 12 cross-border smuggling tunnels have been uncovered since Friday.

The military believes militants have been planning to use the tunnels to smuggle in more advanced weapons, such as anti-aircraft missiles and rockets that could hit Israeli cities from Gaza. He said no such weapons had been found.

Palestinians denounced the raids as part of an Israeli war against them.

In a statement, the human rights group Amnesty International denounced Israel's destruction of houses in Rafah, calling the operation a "war crime" and "grave violation of international human rights."

Meanwhile, Pentagon adviser Richard Perle told a conference in Jerusalem on Tuesday that an Oct. 5 Israeli attack on an alleged training camp for Palestinian militants inside Syria was long overdue. Perle did not rule out U.S. military action against Syria.

Perle also said he hoped the Israeli strike meant Israel was adopting a policy closer to the Bush doctrine of grouping terrorists together with states that harbor them.

"I was happy to see that Israel has now taken a similar step in responding to acts of terror that originate in Lebanese territory by going to the rulers of Lebanon in Damascus," he said.

Israeli warplanes hit the base near Damascus after a Palestinian suicide bomber killed 20 in the Israeli port city of Haifa. Syrians said the base was long abandoned and denounced the Israeli strike, the first deep in Syrian territory since the 1973 Mideast war.