At least three explosions, as well as heavy gunfire, were heard in the Zimbabwe capital of Harare early Wednesday, according to local witnesses.
Witnesses also said military vehicles and soldiers were on the streets early Wednesday, hours after soldiers took over Zimbabwe's state broadcaster, ZBC. Local residents said instead of the usual 11 p.m. newscast, music videos were played instead.
A spokesman at the U.S. embassy in Harare told VOA the streets appeared calm overnight Wednesday and had no confirmed sightings of military vehicles. The embassy warned Americans via its web site to "shelter in their residences" and work from home on Wednesday. They said the embassy will be minimally staffed and closed to the public.
On Tuesday, Zimbabwe's ruling party has accused the armed forces chief of "treasonable conduct" after he threatened to intervene in the country's political affairs.
The statement from the ZANU-PF party was released amid worries that the military might be taking action to oust longtime President Robert Mugabe.
Witnesses reported tanks and armed personnel carriers moving on roads outside the capital; however, Harare was calm and embassies issued no security alerts for their citizens.
A spokesman for the State Department told VOA, "We are aware of the reports and are monitoring the situation."
The current tension was sparked last week when Mugabe fired his deputy, Emmerson Mnangagwa, and accused him of disloyalty and plotting to seize power. Many observers saw the move as a step toward the installation of Mugabe's wife, Grace Mugabe, as vice president. That would put the first lady in position to become president when her 93-year-old husband retires or dies.
At a Monday news conference, the head of Zimbabwe's armed forces, General Constantino Chiwenga, warned he would "step in" unless Mugabe stopped trying to purge the ruling ZANU-PF party of Mnangagwa supporters. Dozens have been arrested since the vice president was fired on November 5.
Tuesday's ZANU-PF statement, signed by party information secretary Simon Khaya Moyo, said that Chiwenga's comments were "clearly calculated to disturb national peace and stability" and meant to "incite insurrection and violent challenge to the Constitutional Order."
President Mugabe has ruled Zimbabwe since the country won independence from Britain in 1980.
Mnangagwa, 75, was seen for years as a likely successor to the president, and maintains strong backing in the army. He is now believed to be in South Africa.
Grace Mugabe, 52, has support in the party's youth wing and is believed to have engineered the firing of another vice president, Joice Mujuru, in 2014.
VOA's Cindy Saine, Anita Powell, Kenneth Schwartz contributed to this report.
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