Four Yemeni policemen were killed in clashes with Islamist fighters during a major government offensive against wanted militants in the south of the country on Saturday, witnesses told a foreign news agency. The deadly shootout erupted in Jaar, northeast of the port city of Aden, where police had been hunting for wanted members of jihadist groups. "This campaign comes after dissident elements attacked members of the security forces and government interests, and disrupted peace and security over the past few weeks," a Jaar security official told foreign news agency. A passerby and seven policemen were also wounded in the fighting, with two in a critical condition, a local hospital source said.