A group of 400 Kenyan security forces have arrived in Haiti, the first wave of a large United Nations-approved security force meant to retake the country from gang rule.

The security forces, dressed in military fatigues and white helmets, landed at Haiti’s Toussaint Louverture International Airport on Tuesday. They are part of an effort, requested by former Prime Minister Ariel Henry 18 months ago, to retake control from a scourge of gang violence. Over 2,500 troops could take part in the effort.