More than 350 people have been killed in lynchings by local vigilante and "self-defense" groups in Haiti since April, a United Nations spokesperson said on Friday, as civilian defense movements attempt to battle escalating gang warfare.

Ravina Shamdasan, a spokesperson for the U.N. High Commissioner for Human Rights, said in a statement that the rise of popular justice, in response to pervasive insecurity, was also leading to violence.

Since April 24, when civilians lynched more than a dozen suspected gang members, at least 310 alleged gang members, 46 members of the public and a police officer have been killed, Shamdasan said.

The report comes after fighting intensified late last week around the capital's heavily populated Carrefour Feuilles neighborhood, where attacks from the Grand Ravine gang prompted close to 5,000 people to flee their homes.

Since the start of this year, the U.N. estimates at least 2,439 people have been killed amid the violence, while some 200,000 people have been internally displaced amid severe food shortages, kidnappings and widespread sexual violence.

Haiti's under-gunned police have struggled against heavily armed gangs, which have dramatically expanded their territory since last year.

The country's unelected government asked for an urgent international security force last October to help bolster its police.

Last month, Kenya said it was prepared to lead such a force, and the U.N. Security Council is expected to vote on this following a ground assessment in coming weeks.

Shamdasan said the High Commissioner for Human Rights called for urgent action regarding the U.N.-backed force, in strict compliance with human rights standards.

"The human rights of the Haitian people must be protected and their suffering alleviated," she said.

(Reporting by Isabel Woodford Editing by Sarah Morland and Mark Potter)