Police in Kwale County on Monday evening shot dead a terror suspect and arrested three others in Kinango sub-county.
Kinango deputy county commissioner Moses Ivuto termed the operation as a major breakthrough by police in fighting terror in the country.
He said four other suspects escaped to their hideouts in Kinango.
Ali Salim was shot dead as he tried to escape accompanied by his colleague, Shadrack Mondao Kaya who was arrested by police.
Police recovered one hand grenade, knives among other assorted weapons, and a motorbike believed to have been stolen from a boda boda operator who was killed last weekend.
Ivuto said the eight suspects are believed to be behind the killing of Nyumba Kumi elders in Bongwe village, Diani last month.
He noted that on Sunday, police arrested two others suspects identified as Ibrahim Mohamed Abdi, 17, and Hamisi Kassim 16,,who were arrested in their hideout in Kabigoni forest after a tip off from the public.
Police are now hunting down the other four suspects who escaped.