An Indonesian court jailed three ethnic Uighurs from China for six years each for trying to link up with a pro-Islamic State in Iraq and Syria (ISIS) terror group in Central Sulawesi led by Indonesia's most- wanted terrorist Santoso.
The trio - Ahmet Mahmud, 20, Altinci Bayyram, 28, and Abdul Basit Tuzer, 30 - were also fined a total of 100 million rupiah (S$10,000) for immigration offences.
Using fake passports, the trio, together with Ahmat Bozolgan alias Hamzah, 27, entered Indonesia illegally through the Nunukan regency in North Kalimantan by boat from Malaysia. They were caught in Poso, Central Sulawesi, last September and went on trial in March.
The trio left China's north-western Xinjiang region last August and travelled to Cambodia and then Thailand. In Bangkok, they met Ahmat Bozolgan, who passed them forged Turkish passports.
The group travelled to Kuala Lumpur, where they obtained visas from the Indonesian embassy.
Ahmat Bozolgan was tried separately and the court will hand down its verdict on July 29.
Yesterday, presiding judge Kun Marioso said a few "clues" helped the three-judge panel to reach its verdict. One was a video showing militants carrying weapons in a jungle and pledging allegiance to ISIS.
It was uploaded by Arif Tuban, one of Santoso's aides, to an account belonging to Abu Jandal, an Indonesian who is in Syria fighting with the ISIS.
The video proved that Santoso's group was still active.
Another clue was also a video, found in Arif Tuban's laptop computer, which showed Santoso saying there would be Muslim fighters heading to Indonesia.
"Santoso announced that he would welcome Islamic fighters from abroad and would open the routes towards him," Mr Kun said.
The judge added that the authorities also found notes containing poems in Arabic which described the militants' commitment to waging war against infidels and leaving their families to do so.
Another vital clue came from a witness who testified that the four Uighurs had stayed in the same boarding house in Bandung, West Java, as a man who attended a paramilitary training camp run by Santoso's group .
Called Mujahidin Indonesia Timur, the group aims to establish an Islamic state in Indonesia by eliminating the police and infidels, whom they see as getting in the way of their efforts.
The terror group is responsible for a series of attacks in Poso, which included killing policemen and staging bomb attacks at a police station.
Mr Asludin Hatjani, a lawyer for the Uighurs, said he will meet his clients to see if they want to appeal against the sentences.
Mr Adhe Bhakti, a researcher at the Centre for Radicalism and Deradicalisation Studies, told The Straits Times: "The judges used clues as the basis for the verdict. Clues can be considered as evidence in a terrorism case, according to our anti-terrorism law."
Indonesia, the world's most populous Muslim-majority country, succeeded in eradicating major terrorist networks in the past decade. But minority radical fringe groups are still active, with some pledging allegiance to ISIS.
Uighurs were in the news last week when Thailand deported nearly 100 of them to China.
The Chinese authorities said some of them had planned to join militants in Syria and Iraq.