Cath Hart and Samantha Maiden – A Papuan student activist was allegedly stabbed to death by Indonesian police after he was caught trying to flee to Australia along with 21 other students last month.

As the Howard Government faces a backbench revolt over proposals to force all asylum-seekers who arrive in Australia by boat into offshore detention centres, new claims have been made of brutality in the strife-torn province.

The latest allegations, which were aired on SBS's Dateline last night, follow the diplomatic rift between Jakarta and Canberra over the protection visas given to 42 Papuans in March.

Immigration Minister Amanda Vanstone, who will table the new legislation today to force all boatpeople who arrive in Australia into offshore processing centres, is expected to confirm the Government will send the controversial reforms to a Senate inquiry.

Documentary maker Mark Davis took eyewitness accounts for the program from Papuans, who said many more were planning to flee to Australia. Three Papuans were detained last weekend after they were found near Boigu Island in the Torres Strait in a boat waving an independence flag.

"There will be more – these people are either dead or 10 years in prison, so they're going to come here," Davis said. The group of 22 students cast off in a boat on April 20, but their vessel sank after a pursuit by two Indonesian police vessels.

The survivors claim the police stabbed to death Benediktus Dimi while he was in the water. "He was stabbed here and here," a survivor called Melianus said, pointing to his arm and the left side of his chest.

"He was stabbed by the military, just like that," another survivor said. Indonesia police claim Mr Dimi drowned and was not killed.