Kuwaiti security forces are hunting a number of key militant suspects after a recent spate of al Qaeda-linked violence in the U.S.-allied oil-rich Gulf state, security sources said on Friday. Confessions of captured militants revealed they were planning suicide attacks against U.S. forces in Kuwait as well as Kuwait's state security forces, the sources said. Kuwaiti security killed five suspected al Qaeda militants and captured three, including the group's leader, on Monday in the fourth such gun battle in the country last month. State security officer Hamad al-Samhan, one of three police, wounded in the clash, died in hospital on Friday, the sources said. Kuwait's leaders had vowed to finish off the militants behind the violence, mostly Kuwaitis with links to jihadists in neighbouring Iraq and Saudi Arabia. The militants were being hunted based on information gathered from the interrogation of captured militants who include Amer al-Enezi, the cell's suspected spiritual leader who is believed to have al Qaeda links, they said. The suspects being pursued include two senior militants -- Kuwaitis Khaled al-Dosari and Mohsen al-Fadli -- both sought for previous suspected involvement in extremist Islamist activity. "The raids and searches continue," one source told Reuters. "There are wanted people whose names are mentioned during the interrogations and they may have links to this network." He said militant suicide bombers had been planning to target U.S. convoys and other U.S. citizens in the country.