Gunmen ambushed a police patrol in Pakistan's northwest Monday, killing four officers while a roadside bomb killed a member of another security unit elsewhere in the region. Two officers died during the ambush on the outskirts of Peshawar city early Monday, while two others died later at a hospital from multiple bullet wounds, senior police official Nisar Khan said. The roadside bomb targeted a vehicle of the Frontier Constabulary in the Bannu area, killing one and wounding seven constabulary officers, local hospital official Mohammad Jawed was quoted as saying by the Associated Press. One of the wounded was a senior constabulary officer, Bannu police chief Iqbal Marwat said.