Heavily armed gang members who once ran Haiti's largest slum like warlords have returned with a vengeance since Tuesday's earthquake damaged the National Penitentiary allowing 3,000 inmates to break out. The pacification of Cite Soleil had been one of President Rene Prevail's few undisputed achievements since taking office in 2006, until the quake devastated Port-au-Prince.

"It's only natural that they would come back here. This has always been their stronghold," said a Haitian police officer in the teeming warren of shacks, alleys and open sewers that is home to more than 300,000 people.

He and other policemen, who asked not to be identified because they were not authorised to speak about the volatile situation in Cite Soleil, said notorious armed gangs had been making their presence felt here since the quake.

If large-scale violence erupts here amid the chaos and looting that has grown by the hour in Port-au-Prince since the temblor, it could pose a major challenge to efforts to re-establish law and order throughout the Haitian capital.

Copyright Reuters, 2010