“I’ve seen them get down from their truck, stop traffic and beat people up,” said Carlos Mobealla, the mayor of a portion of the capital.

“They took two people away; they didn’t come back,” said Aimée Wilfried Mahoroka, a construction worker in Bangui, who was among five people picked up by cruising fighters on a recent Saturday downtown. The five had been shut up in a house requisitioned by the rebels; two were removed from the room, and when the Seleka returned, they were carrying buckets with blood in them, said Mr. Mahoroka, adding that he later managed to leap from the rebels’ pickup truck.

The United States abandoned its embassy here months ago. “Now we are in a phantom state,” said a Western diplomat who has stayed on here. “It’s extremely dangerous. People are afraid for the future, and they are right.”

The crisis has been a long time in the making. Isolated in the middle of the continent, with few roads out or natural resources, the Central African Republic became independent in 1960 after a brutal six-decade colonial reign by France. But the former colonial power would continue to meddle in the cycles of coups, rebellions and violent transitions that have marked the country’s history ever since, though it is taking a back seat now. “Weariness” has overtaken Western officials faced with the turmoil, the diplomat here said.

The state had already nearly disappeared under the corrupt rule of Mr. Bozizé, who was president for 10 years before being chased out by the rebels. He had led a previous rebellion himself and is now in hiding, probably in the region, though even the government says that is not certain.

The rebels emerged from the barren, more-Muslim north, angered at the neglect of a region inaccessible from the capital for half of the year because of heavy rains and poor roads, accusing the president of reneging on an agreement to integrate some of their fighters into the army.

“No schools, no roads, really — it’s chaos,” said Abdel Kadir Kalil, a Seleka commander, explaining why he had taken up arms. Carrying an elaborately carved ceremonial cane on the terrace of the Libyan-built five-star hotel where he lives here, he added, “We wanted to develop the country, but the ex-president, Bozizé, he ignored our projects.”