As US Secretary of State Hillary Clinton arrived in Burma's capital Naypyidaw last week, government troops killed civilians and burned houses in a Christian-majority state about 450 miles away.

Compass Direct reported a story by Kachin News Group detailing how Burmese soldiers killed a woman and injured six other villagers on November 30 as they fired four rounds of mortar shells at civilians in the Tarlawgyi area of Kachin state's Waingmaw Township.

Another battalion burned down 10 homes in Nam Wai village and five more in neighbouring Hpa Ke village, both in Dawhpumyang sub-township in Bhamo district, Kachin News added.

The killing and arson followed two explosions that killed a student and injured another the previous night in the state's capital, Myitkyina.

Local residents suspected government agents planted the bombs, a Kachin journalist told Compass Direct by phone on condition of anonymity. The twin blasts rocked the state capital days after a powerful explosion killed seven children and three internally displaced Kachin people and injured 16 other children at an orphanage on November 13 in Myitkyina's Thida Ward.

Compass Direct said two sons and a grandson of a Christian couple who run the orphanage in their home were among those killed, but police arrested the family, alleging they had detonated it.

The attacks left civilians in Kachin, where an estimated 90 per cent of the 1.2 million people are Christians "terrified", the report said.

About 90 per cent of the roughly 56 million people in Burma are Buddhist, mostly from the Burman ethnic group.