Three police officers are in Thailand to work with police there in the hunt for a senior Free Aceh Movement (GAM) rebel, police spokesman Zainuri Lubis said.

He described Zakaria Zaman bin Kaman as GAM's "defence minister," responsible for smuggling weapons to Aceh from Thailand, and added: "We hope for a good outcome."

In the provincial capital Banda Aceh, police said students and other activists who support the separatist guerrillas would face subversion charges that can carry the death penalty.

"We will use the (criminal code) article on subversion, which carries up to the death sentence, against them," said Sayed Husaini, police spokesman in the province where a major military assault against the rebels is in its third week.

Husaini said police have a sizeable wanted list of activists who support or assist GAM and also have evidence against them.

Many are from the Ar-Raniry State Institute for Religious Sciences in Banda Aceh or members of non-governmental organisations (NGOs), he said.

Up to 40,000 police and soldiers are confronting an estimated 5,000 rebels in Aceh in Indonesia's biggest military operation for a quarter-century.

Jakarta is also mounting a diplomatic offensive. It says it will send a team to Sweden this week to try to persuade Stockholm to clamp down on GAM's exiled top leadership there.

Meanwhile, Jakarta Tuesday rejected British appeals not to use British-made Hawk aircraft in Aceh.

Visiting Foreign Office Minister Mike O'Brien raised the issue during talks with Foreign Minister Hassan Wirayuda, said ministry spokesman Marty Natalegawa.

From the British point of view, Natalegawa said, the use of Hawks was "a violation of a previously made agreement."

"From the foreign ministry perspective, we conveyed to (O'Brien) that there was no such agreement and whatever is being carried out in the Aceh operation is not an offensive action," Natalegawa said.

Britain says it supplied the trainer/fighter aircraft on the understanding they would not be used for offensive operations.

The military, which has a record of gross rights abuses in the 1990s in Aceh, has said it will try to protect civilians this time.

It has denied reports from some villagers that troops shot civilians dead in an operation on May 21 and has described those killed as GAM members.

Also Tuesday, three soldiers accused of beating up three villagers during a separate search for rebels faced a court-martial. They could face up to two years and four months in jail if convicted.

A military prosecutor told the court the soldiers lost their tempers after villagers at Lawang in Bireuen district on May 27 claimed they did not know anything about GAM members in the area.

Three other soldiers, including a second lieutenant, are awaiting trial over the same incident while another soldier is to be tried for alleged extortion.

A headmistress was among latest victims of violence in the province.

Gunmen shot her dead and critically wounded her daughter at their home in Bireuen district late on Monday, said local police chief Laksa Widyana.

Residents said the bullet-riddled body of another school employee was found on a roadside in Aceh Tamiang early Tuesday.

Widyana said public transport stopped operating Tuesday between Bireuen and Lhokseumawe following threats from rebels.

GAM has been fighting for an independent state since 1976. Some 10,000 people, mostly civilians, have been killed since then.

WAR.WIRE