Johannesburg — Multiple security sources in the West African nation of Niger told CBS News on Wednesday that an American national was kidnapped from his home in the capital Niamey on Tuesday night.

They said the abduction by unknown assailants took place only about 100 yards from the presidential palace in Niamey, where ousted President Mohamed Bazoum has been held since he was toppled by a coup more than two years ago.

The U.S. Embassy in Niamey issued a security alert Wednesday warning that American citizens "remain at a heightened risk of kidnapping throughout Niger, including in the capital city."

Sources told CBS News the man abducted on Tuesday is a missionary who has worked for years for a U.S.-based charity.

CBS News has asked the U.S. State Department for any information i

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