Madiun, East Java – A sergeant on Monday became the first Indonesian soldier to be convicted of people-smuggling as Jakarta tries to stem the flow of asylum seekers traveling via the country to Australia.

Separately, prosecutors demanded prison terms of seven to eight years for four military officers if found guilty in the same case, when an asylum seeker boat capsized en route to Australia, killing more than 200 people.

Indonesia's House of Representatives in April last year passed a long-awaited law criminalizing people-smuggling.

Second Sgt. Ilmun Abdul Said had been "proven legally and convincingly guilty for helping to smuggle hundreds of illegal migrants out of Indonesia," chief judge Muhammad Afandi told the Madiun district military court in East Java province.

"He is sentenced to six years in prison and fined Rp 500 million ($52,000)... He is also dismissed from the military service." Said, 36, told the court he would appeal the verdict.

Last December's incident is believed to be the largest loss of life from a sinking of one of the many boats packed with Asian and Middle Eastern migrants who undertake the often perilous voyage to Australia via Indonesia. Most of the victims were from Iran and Afghanistan.

Local media reports say that asylum seekers pass through checkpoints and board boats bound for Australia with help from corrupt military or police officials in return for cash. Said's sentence was less than the eight years sought by prosecutors under the new law, which carries up to 15 years in prison.

He was "the first Indonesian military officer in history to be convicted of people-smuggling," Afandi told reporters after the trial. Local media reported previous convictions involving only non-military personnel.

Judges did not spell out Said's role, but in earlier trials chief prosecutor Upang Juwaeni said he "helped to find spots where small boats could come ashore, pick up the migrants and take them to bigger boats waiting at sea heading to Australia." Afandi said the capsized boat was the seventh Said had helped to arrange.

Australia is facing a steady influx of asylum seekers arriving by boat, many of whom use Indonesia as a transit hub and pay people-smugglers for passage on leaky wooden vessels after fleeing their home countries. Hundreds of boatpeople have died en route to Australia this year.