Police in Haiti have arrested a former senator who has been charged with conspiring against the state and financing criminal organisations.

Nenel Cassy was arrested on Saturday while he was at a restaurant in Petionville, a wealthy district of the capital, Port-au Prince, Haiti's National Police said in a post published on Facebook. The police shared photos of the former senator in handcuffs, next to heavily armed officers wearing ski masks.

Cassy, who was designated as a corrupt actor by the US State Department in 2023, was accused by Haiti's police in February of backing gang members who launched attacks on Kenscoff, a wealthy neighbourhood 10 kilometres outside Port-su-Prince, that had been largely untouched by Haiti's gang violence.

Dozens of people were killed in the February attacks including farmers who worked in the nearby hills and a 2-month-old baby.

Gangs control 90 per cent of Haiti's capital, according to the United Nations, and in recent months they have been launching attacks on previously peaceful communities in order to seize more territory.

More than 5,6000 people were reported killed in Haiti last year, with gang violence leaving more than one million people homeless in recent years, according to the UN.