President Joseph Kabila has flown to the Democratic Republic of Congo's second city, Lubumbashi, after reports of an armed uprising in the area.
Joseph Kabila succeeded his father in 2001
Some 109 people, including soldiers, have been arrested in recent days.
Officials talk of an "aborted insurrection attempt", while there are reports of a secessionist uprising in the resource-rich Katanga province.
Katanga's leaders failed in their attempt to secede in the 1960s, after a three-year war.
A presidential aide told the BBC that Mr Kabila had gone to Lubumbashi accompanied by the defence minister to reaffirm his authority in the town.
His father Laurent Kabila came from Katanga.
Gregoire Molamba, of the Katanga-based Centre for Human Rights, said that there had been arrests in Kinshasa, Kananga, Mbuji Mayi and Lubumbashi in the past few days, with some being questioned by the intelligence services in Lubumbashi.
Acting Katanga governor Nkunda Milandou told the BBC that the people arrested are being questioned over their participation in a network whose aim was to destabilize the Congolese institutions.
But he has refused to give details.
Among those arrested are Andre Tshombe, the leader of a local political party who is also a relative and admirer of former Congolese prime minister Moise Tshombe, the leader of Katanga's 1960s secessionists.
Sources say that the vast majority of those arrested are from ethnic groups from the south of Katanga.
With its vast deposits of copper and cobalt, Katanga is DR Congo's richest province.