By Christian Elion
BRAZZAVILLE, April 4 (Reuters) – Gun battles shook the capital of Congo Republic on Monday, shattering a relative calm that had followed President Denis Sassou Nguesso’s re-election in a disputed vote last month.
Former members of the “Ninja” militia that fought Sassou Nguesso in a 1997 civil war raided and set alight military, police and local government offices but the attacks have been contained, government spokesman Thierry Moungalla said.

Gunfire had died down by mid-afternoon as security forces blocked access to southern Brazzaville, where exchanges of heavy calibre fire between police and unidentified fighters broke out around 3 a.m. local time (0200 GMT), witnesses said.
The government did not say whether anyone was killed in the fighting. Thousands of residents streamed north, many carrying their possessions on their heads.
Sassou Nguesso, who has ruled the oil-producing central African country for 32 of the past 37 years, regularly presents himself as a bulwark of stability in a turbulent region. State-run television on Monday broadcast images of damage from the fighting alongside reminders of Congo’s violent past.
The fighting between security forces and unidentified gunmen was some of the worst to hit Brazzaville since 1997, when Sassou Nguesso returned to power after months of urban warfare between rival militia groups in the capital. He had previously ruled the country from 1979 until 1992, when he lost an election.
Sassou Nguesso won re-election on March 20 after pushing through constitutional changes in an October referendum to remove age and term limits that would have prevented him from standing again.
Opposition leader Guy-Brice Parfait Kolelas, whose father led the Ninjas during the civil war, came second in the election. The Ninjas signed a peace accord with the government in 2003 after years of sporadic clashes, though rivalries persist along regional and ethnic lines.
At least 18 people were killed by security forces during opposition demonstrations against the referendum changes.