TA group of military officers say they have seized control of Guinea-Bissau amid reports that the president, Umaro Sissoco Embaló, has been arrested.
Shortly after gunshots were heard in the capital, Bissau, government sources told the BBC that Embaló had been detained.
The officers then appeared on state TV, saying they had suspended the electoral process, as the West African nation awaited the outcome of Sunday's presidential election.
They said they were acting to thwart a plot by unnamed politicians who had "the support of a well-known drug baron" to destabilise the country, and announced the closure of its borders and imposed a night-time curfew.
