firefighters they believe are linked to this suicide bombing in january that killed four americans. the bombing killed green beret jonathan farmer, former navy skill, scott water and two language specialists. reporter: good morning. such important news for the families of the american and the u.s. military. a u.s. defense official tells cnn this morning in february now the sdf, syrian democratic forces, backed by the u.s. and syria did capture up to five isis militants they believe were involved in the planning and execution of that suicide attack in january in northern syria that killed four americans and several syrians when a suicide bomber detonated a huge bomb near a restaurant there. this information was first reported by reuters.