Jakarta - An Indonesian court on Tuesday sentenced three Islamic militants to 12 years each for plotting terrorist attacks and killing a Christian teacher.

The three men - Sugianto, Adityawarman and Heri Purwanto - were among 10 people arrested in the South Sumatran provincial capital Palembang last year for alleged involvement in a plot to bomb a cafe and to kill Christian priests as part of a jihad campaign waged by the Jemaah Islamiyah regional militant group.

Judges at the South Jakarta district court found the three guilty of involvement in the murder of a Christian teacher in Palembang in 2007 and a conspiracy to blow up a cafe in neighboring West Sumatra the previous year.

Prosecutors said the militants aborted the plan after realizing that the cafe was frequented by women wearing Muslim headscarves.

Prosecutors have sought 20 years in prison for a Singaporean Muslim militant, Muhammad Hasan bin Zaynudin, suspected to be the leader of the South Sumatra cell.

Hasan has admitted he had met al-Qaeda leader Osama bin Laden and undergone military training in Afghanistan.

During the raids on the militants in June and July, police seized 20 assembled bombs, dozens of kilograms of potassium chlorate and other explosive materials as well as several hand grenades.

The country's anti-terrorism police have arrested about 300 militants since the 2002 Bali bombings, which killed 202 people, but authorities said the threat of more attacks remained even though the country has not suffered an attack since 2005.(dpa)