Ghana's Defence Minister Edward Omane Boamah died in a military helicopter crash on Wednesday along with four other officials and three airforce crew, the government said.
Julius Debrah, President John Mahama's chief of staff, told a press conference that the crash in which Boamah, Environment, Science and Technology Minister Ibrahim Murtala Muhammed and others were killed was a national tragedy.

"The president and government extend our condolences and sympathies to the families of our comrades and the servicemen who died in service to the country," Debrah said.

Authorities did not immediately give an explanation for what might have caused the crash.

Earlier Ghana's armed forces said radar contact had been lost with a Z9 airforce helicopter.

Boamah, a former communications minister, was tapped to serve as defence minister in January after Mahama returned to power.

His replacement will take on a complex security file that includes both external and internal threats.

Like other coastal West African countries, Ghana faces threats from Islamist groups active in the Sahel that have tried to push south from landlocked Burkina Faso and Mali where they stage frequent deadly attacks.

A spokesperson for Mahama said last month that Ghana had deployed more soldiers to a northeastern region where a long-running conflict over chieftancy has fuelled recent violence, including attacks on schools.