Reports from Zimbabwe: Army vehicles in capital city, explosions heard

Reports of explosions in Zimbabwe's capital city of Harare could be more evidence the African country is on the verge of a coup.

Soldiers reportedly took over the national broadcaster's headquarters as military vehicles were seen in the streets Tuesday evening. That's an escalation from earlier in the day, when tanks and other military vehicles were seen on streets outside Harare.

President Robert Mugabe has quickly lost the favor of the country's military after he fired the sitting vice president. That move was widely seen as a way to help his wife's political aspirations to succeed him.

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But Grace Mugabe is in her early 50s, which means she was too young to have had any role in the 1970s liberation war against minority-white rule. That makes her an unpopular candidate with military leaders, who have said they would only back a leader who was involved in the war.

In response to the political uncertainty, the U.S. embassy in Zimbabwe will be closed to the public tomorrow.