The US embassy in Kinshasa will on Thursday be closed to the public for a fourth day following "credible and precise information" about a possible terrorist threat, a month ahead of the Democratic Republic of Congo's presidential election.
In a statement on its website, the embassy urged "US citizens in Kinshasa and throughout DR Congo to maintain a high level of vigilance".
"The US embassy in Kinshasa will remain closed to the public on Thursday, November 29" due to "credible and precise information on a possible terrorist threat" targeting "US facilities in Kinshasa", it added.
On Monday, after the embassy first closed and warned US nationals to keep a low profile, Congolese authorities described its reaction as "useless psychosis".
After two years of setbacks, broken promises and delays, the DR Congo last week kicked off the campaign for a crucial election that could alleviate - or perhaps worsen - the decades-long crisis.
Voters on December 23 will choose a successor to outgoing President Joseph Kabila, who has constitutionally remained in power as caretaker leader even though his second and final elected term ended nearly two years ago.
At stake in the vote is the political future of a mineral-rich country that has never known a peaceful transition of power since independence from Belgium in 1960.
Eastern DR Congo is ravaged by decades of inter-ethnic bloodshed and militia violence, as well as a deadly Ebola outbreak, testing a large UN peacekeeping mission deployed in the country.
The United States has called on the African nation to seize its "historic opportunity" to hold a "credible election" that could ease its humanitarian problems and boost stability.