The multiple attacks on Monday saw armed men take reporters hostage and fire shots at the airport, which is on the outskirts of Kinshasa.
Before transmission was shut down at RTNC, two gunmen appeared on camera to deliver what appeared to be a political message against President Joseph Kabila's government.
"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.
In central Kinshasa, the streets emptied and shopkeepers closed their shutters, Al Jazeera reported.
"They are armed with machetes and guns. They have taken reporters hostage. An operation is under way to dislodge them," police spokesman colonel Mwana Mputu told the news agency AFP.
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."
It is not clear if the two attacks are linked.