A citizen of the United States of America working in Zimbabwe has been arrested by police for allegedly referring to President Robert Mugabe sick and selfish in a retweet.

In a report by Aljazera, the police arrested the US citizen, Martha O'Donovan, for allegedly "insulting" President Robert Mugabe in a tweet she shared.

Martha had reportedly re-tweeted a post which apparently referred to Mugabe as a "selfish man and sick man", Zimbabwe Lawyers for Human Rights (ZLHR), which is representing O'Donovan, said in a tweet on Friday.

The Magamba TV member of staff, was arrested on Friday, November 3, 2017 during a dawn raid on her home in Harare, the television station said in a statement.

Zimbabwe Republic Police "says Martha O'Donovan insulted Mugabe when she allegedly tweeted that 'We are being led by a selfish man and sick man'", ZLHR tweeted. The post shared by O'Donovan did not refer to Mugabe by name.

ZLHR also said on Twitter that O'Donovan is being charged with "undermining [the] authority of or insulting [the] president".

Mugabe controls social media

Since the creation of the Ministry of Cyber Security in Zimbabwe in October 2017, Martha's arrest is the first arrest.

The new ministry focuses on crimes on social media and the worldwide web in general, in advance of the 2018 presidential election.

Amnesty International condemned the arrest, saying it "marks the start of a sinister new chapter in the Zimbabwean government's clampdown on freedom of speech - and the new battleground is social media".