Ghana?s ministers of defence and environment have died in a military helicopter crash in the central Ashanti region, along with six other people, a government spokesperson says.

Defence Minister Edward Omane Boamah and Environment, Science and Technology Minister Ibrahim Murtala Muhammed, 50, were killed in the crash, which Chief of Staff Julius Debrah described as a ?national tragedy?.

Earlier, the Ghana Armed Forces said the aircraft, which was carrying three crew and five passengers, had gone ?off the radar?.

It had taken off from the capital, Accra, at 09:12 local time (and GMT) and was heading to the town of Obuasi for an event to tackle illegal mining.

Images purportedly showing the charred remains of the helicopter are circulating on social media.

The authorities have not confirmed the cause of the crash.

The chief of staff has directed the country?s flags to fly at half-mast.

He extended condolences to ?the servicemen who died in service to the country,? on behalf of President John Dramani Mahama and the government.

Ghana?s Deputy National Security Coordinator and former Agriculture Minister Alhaji Muniru Mohammed was also among the dead, along with Samuel Sarpong, Vice-Chairman of the governing National Democratic Congress party.

The crew members were named as Squadron Leader Peter Bafemi Anala, Flying Officer Manin Twum-Ampadu, and Sergeant Ernest Addo Mensah.

President Mahama was feeling ?down, down emotionally?, Education Minister Haruna Iddrisu was cited as saying by news agency AFP.

Boamah served under Mahama?s previous government as communications minister and before that he was minister of environment. As defence minster he tackled jihadist activity that was brewing in the northern border in Burkina Faso.

Boamah?s book A Peaceful Man In An African Democracy, about former president John Atta Mills, was due to come out later in the year.

Muhammed was at the forefront of the battle against illegal gold mining, which has wrecked the environment and contaminated rivers and lakes.

Protests against the practice, known locally as Galamsey, peaked during Mahama?s run for the presidency last year. (BBC)

?Ghana Defence Minister Edward Omane Boamah (l) and Environment, Science and Technology Minister Ibrahim Murtala Muhammed

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