In the predawn hours on a Sunday in late July, members of one of Haiti’s largest armed gangs attacked the town of Ganthier, about 25 miles east of the capital and on a road that the authorities say is used to smuggle weapons.

When police reinforcements arrived in armored vehicles hours later, officers found the streets deserted, the gang members having left after destroying Ganthier’s police station and torturing and killing several residents, according to the town’s mayor and the police.

“The whole town of Ganthier is emptied; there is no one left,” the mayor, Jean Vilonor Victor, told The New York Times.

Weeks after the arrival of a United Nations-backed international security force in Haiti, the gangs who have brought the capital, Port-au-Prince, and other regions in the country to their knees show no signs of letting up.

The international effort to reinforce the Haitian police and a transitional government has alleviated conditions in some sections of Port-au-Prince, experts say, but gang members have refocused their attacks on the outskirts, marauding towns that had escaped their campaign of killings, kidnappings and rape.

The attack on Ganthier, a town of 60,000 people on a major highway linking the capital to the border with the Dominican Republic, is emblematic of the persistent security problem Haiti’s government faces as it tries to rebuild the shattered country, which has seen three years of violence, mass migration and economic ruin.