Jakarta – Lawyers of the six convicted murderers of PT Freeport Indonesia's employees Thursday submitted appeal documents to the Supreme Court over those sentences by lower courts.

Two American teachers and an Indonesian colleague were killed on Aug. 31, 2002 when gunmen ambushed their convoy near the American-owned Grasberg gold and copper mine near the Papuan provincial town of Timika.

Seven people were found guilty over the incident. They are Antonius Wamang, Agustinus Anggaibak, Yulianus Deikme, Ishak Onawame, Esau Onawame, Hardi Sugumol, and Yairus Kiwak alias Kibak. Hardi died in a hospital.

Antonius, who was found guilty as mastermind of the incident got life sentence in the Central Jakarta District Court and the verdict was affirmed by the Jakarta High Court.

Agustinus and Yulianus were sentenced to six year jail term by the Central Jakarta District Court, but the Jakarta High Court granted tougher punishment with 8 years in jail.

Meanwhile, each of the four other people were sentenced to 18 months in jail by district court, but the Jakarta High Court changed the sentences into five years jail terms.

Ecoline Situmorang, the lawyer of the six people, questioned the additional sentences for his clients, saying that it only based on a consideration that the district court's sentence is too light.

"Such a consideration is strange. Politics seems behind it," Ecoline was quoted by Antara news agency as saying.