Zimbabwe's President Emmerson Mnangagwa has replaced the chief of the Air Force as the country remains in heightened alert following an anonymous threat of attack against the country's airports.

Air Marshal Elson Moyo has been sent into retirement and will be replaced by Air Vice Marshal John Jacob Nzvede, the presidency announced on Friday.

The changes take effect on 15 March.

It comes hours after Mnangagwa abandoned a trip to Victoria Falls for a planned address at a conference on renewable energy to allow for investigations into the threat.

'Credible threat'

On Friday morning, Zimbabwe airport authorities were made aware of an email sent through Fastjet Airline claiming a "credible bomb/firearm threat" targeting Zimbabwean airports, according to an earlier announcement by the president's spokesperson.

The country's security forces are on heightened alert as the threats were considered "serious" and nothing "should be left to chance", it said.

The Civil Aviation Authority of Zimbabwe said that the incident had forced some flights to divert or delay landing, and more disruptions were likely “to allow for the continuous monitoring of the environment.”

President's plane U-turn

Local media had reported earlier on Friday that Mnangagwa's private plane made a U-turn minutes before landing at Victoria Falls airport, and went back to the capital Harare.

An Air Zimbabwe plane with passengers on board was detained at Victoria Falls, while a Kenyan Airways flight rerouted to land in Livingstone, Zambia, according to local news reports.

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