Mnangagwa and Grace Mugabe have been seen as political rivals since he was removed from his post as vice president prior to the coup that led to her husband's resignation.
About 400 workers allegedly uprooted trees to dig for gold.
Zimbabwe's Robert Mugabe, untouchable for decades and a hero of African independence, is out. Who's next?
A military takeover seems to herald the last days of Africa's oldest ruler, whose tenor has seen Zimbabwe fall into economic despair.
General Constantino Chiwenga warned of military intervention to back independence figures after President Robert Mugabe purged his prominent second-in-command.
A manhunt is underway after the first lady was heckled at a rally.
Robert Mugabe fired his deputy on Monday, paving the way for his wife Grace to succeed him.
A report that Grace Mugabe donated used underwear to party activists is the latest in a series of embarrassments caused by the first lady.
The first lady may struggle to convince Zimbabweans that she is ready to be president after allegedly beating a model with an extension cord.
Zimbabwe's first lady is trying to dodge allegations of assault, but many are adamant she should be charged.
Zimbabwe's first lady is accused of assault and has failed to show up in court in South Africa, where her husband is now going for a conference.
Grace Mugabe is accused of assaulting a young woman with an extension cord after the woman visited two of the Mugabe sons at a Johannesburg hotel.
Grace Mugabe is one of two leading candidates to succeed the 93-year-old president, who has been in power since 1980.
Grace Mugabe was taken to a local hospital where she was treated for bruising.
Mugabe, the world's oldest head of state at 93, is running for reelection in 2018. If he wins, he'll stay in power until he's 99.
Mugabe's daughter Bona Chikore will help police social media, a platform for vocal opposition to the president, ahead of elections in 2018.
Mugabe's wife and vice-president are thought to be vying to succeed the 92-year-old.
Tsvangirai has stood for election against Robert Mugabe three times in Zimbabwe.