Gunmen have attacked the airport and seized control of the state television headquarters in the capital of Democratic Republic of Congo.
The move appears to be an attempt to seize power by supporters of religious leader Paul Joseph Mukungubila.
Police put a security cordon around the state television building where gunmen had taken several people hostage, journalists told Reuters.
Witnesses also reported shooting at the Tshatshi military camp, close to the Defence Ministry.
DR Congo, a vast country at the heart of Africa, is struggling to emerge from decades of violence and instability, particularly in its mineral-rich east, in which millions of people have died, mostly from hunger and disease.
The country is home to a 21,000-strong United Nations peacekeeping mission (MONUSCO).
Before transmission was shut down at state television, two gunmen appeared on camera to deliver what appeared to be a political message against President Joseph Kabila.
President Kabila took office in 2001 after the assassination of his father Laurent.
"Gideon Mukungubila has come to free you from the slavery of the Rwandan," said the message, according to a Reuters reporter who saw a tape of the transmission.
Gideon is the nickname used for Mukungubila by his followers.
Mukungubila, who calls himself "The prophet of the Eternal", ran unsuccessfully for the presidency against President Kabila in 2006.
He has been an outspoken critic of a peace deal signed this month with the Tutsi-led M23 rebel group in eastern Congo, accusing Mr Kabila's government of bowing to Tutsi interests and pressure from neighbouring Rwanda.
Information Minister Lambert Mende said security forces had the situation under control.
"The attackers presented themselves as supporters of Mukungubila. We are checking because this could be an attempt to fool us," he told Reuters.
In central Kinshasa, the streets emptied and shopkeepers closed their shutters.
A customs official at the international airport on the outskirts of Kinshasa reported heavy gunfire there just minutes after the attack on state television.
"Shooting has started here," the official told Reuters."They are shooting everywhere. We are all hiding."