Armed gunmen also wielding machetes attacked Congo's presidential residence Sunday, and at least nine people were killed during nearly an hour of gunfire, a witness said. The president and his wife were not home at the time of the assault.
President Joseph Kabila, who first inherited the job after his father's assassination, blamed opponents ahead of the elections set for November.
"It is these people who fear facing me in the elections who did this," Kabila said, according to an adviser. "I am handling the situation wisely."
Communications Minister Lambert Mende later appeared on national television and said the matter was under control. He said some of the assailants had been killed or wounded, while others were arrested.
"These people wanted to physically harm the president, but the country and all its institutions are functioning normally," Mende said.
A witness near the presidential residence who spoke on condition of anonymity for fear of retribution reported seeing the bodies of seven attackers and two bodyguards.
While eastern Congo is highly volatile with a myriad of rebel groups and militias who terrorize civilians, such violence in the capital of Kinshasa is more rare.
Kabila first took office after his father, Laurent Kabila, was assassinated in 2001. The younger Kabila was later elected in 2006 in the country's first democratic election. In January, Parliament voted to hold only one round of presidential elections, a move considered to favor Kabila's candidacy by scrapping the chance of a runoff election by allowing a candidate to win with less than 50 percent of votes.
The vast, mineral-rich Central African nation was ravaged by years of dictatorship and civil war, keeping its people from profiting from vast reserves of diamonds, gold and other resources.