Civilian authorities in Pakistan depend heavily on the army during natural calamities such as the floods which have swamped parts of the country this monsoon season.

A helicopter on relief operation in Balochistan was reported missing Monday night with six passengers and crew -- including one of the army's top commanders, Lieutenant-General Sarfraz Ali.

In a statement Tuesday, the military said all aboard had died in a crash they attributed to bad weather.

"All the six officers and soldiers... embraced shahadat (martyrdom)," it said.

Fierce monsoon rains and deadly flooding have hit Pakistan hard this year -- particularly in Balochistan province, bordering Iran and Afghanistan.

At least 478 people have died so far, including 136 in Balochistan.