Armed gangs have stormed the main prison in Haiti's capital Port-au-Prince, releasing many inmates.

The vast majority of about 4,000 men held there have now escaped, a local journalist told BBC News.

Among those detained were gang members charged in connection with the 2021 killing of President Jovenel Moïse.

Violence in Haiti, the poorest country in the Americas, has worsened in recent years. Gangs aiming to oust PM Ariel Henry control 80% of Port-au-Prince.

The latest upsurge in violence began on Thursday when the prime minister travelled to Nairobi to discuss sending a Kenyan-led multinational security force to Haiti.

On Friday, Kenyan President William Ruto said he and Mr Henry had signed an agreement and were working to fast-track the deployment.

In January, the UN said more than 8,400 people were victims of Haiti's gang violence last year, including killings, injuries and kidnappings - more than double the numbers seen in 2022.

Violence has been rife since President Moïse's assassination in 2021. He has not been replaced and elections have not been held since 2016.

Under a deal, elections were to be held and the unelected Mr Henry was due to stand down by 7 February, but that did not happen.

Since he left the country for Kenya, unrest in Port-au-Prince has escalated further, with gang leader Jimmy Chérizier (nicknamed "Barbecue") declaring a coordinated attack to oust the prime minister.

"All of us, the armed groups in the provincial towns and the armed groups in the capital, are united," said the former police officer, who is thought to be behind several massacres in Port-au-Prince.

A wave of shootings in the capital has left four police officers dead and five injured.

At the weekend the French embassy in Haiti advised against travel in and around the capital. Haiti's police union has asked the military to help reinforce the prison.