Myanmar's junta has kept up a deadly military campaign, including airstrikes and artillery assaults, despite announcing a ceasefire after a major earthquake killed thousands in March, according to the United Nations and data from a crisis monitor.

The March 28 quake, the worst natural disaster to hit the impoverished nation in decades, triggered a multi-national relief effort to support hundreds of thousands already ravaged by conflict and repeated international calls to halt the fighting.

On April 2, following similar moves by opposition armed groups, Myanmar's military announced a 20-day ceasefire to support humanitarian relief. On Tuesday, it said the temporary cessation had been extended until April 30 after rare high-level talks led by Malaysia's premier.