Six people were killed when a private airplane crashed south of Haiti's capital Port-au-Prince, local authorities said Saturday.

The aircraft had taken off from the city's airport at 6:57 pm (2257 GMT) on Friday and should have arrived at Jacmel, on Haiti's southern coast, around an hour later, according to the National Civil Aviation Office (NCAO). 

"The plane crashed en route with six people on board," an NCAO incident report said.

Gutenberg Destin, the coordinator of civil protection for Haiti's Ouest Department, confirmed to AFP that all six people on board had perished.

Experts, with the assistance of police, civil protection officers and local authorities, were "working hard to reach the crash scene, in a hard-to-access location," according to the NCAO. 

The cause of the crash wasn't immediately clear. 

With heavily armed gangs controlling the main land route from Port-au-Prince to the southern half of Haiti, charter flights to Jacmel have become increasingly popular -- among the tiny number of Haitians able to afford them.