An insider from Zimbabwe's ruling government has posted information suggesting that longtime president of the African nation Robert Mugabe has collapsed.

Happyton Bonyongwe, the director-general of the Zimbabwean Central Intelligence Organisation, has reportedly tightened security at State House in Zimbabwe, a day after fears for Mr Mugabe's health surfaced, internet commenter Baba Jukwa said.

Zimbabwe's President Robert Mugabe in Harare, in August 2013. Credit:Reuters

Baba Jukwa, an insider in the ruling Zanu-PF party who uses a Facebook page to expose corruption in the regime, on Saturday reported rumours that Mr Mugabe had collapsed.

However, he added that Mr Mugabe's press secretary, George Charamba, had denied that the President was ill.