Four persons, including a tribal elder, were killed when their vehicle was ambushed in Merna area of South Waziristan District of Khyber Pakhtunkhwa on June 3, reports Dawn. District Police officer Shaukat Ali said Malik Sermerjan along with a son, a nephew and two daily wagers was on his way to Shah Alam Bazaar in Merna area when unidentified assailants opened fire at his vehicle in a dry watercourse. Sermerjan, his nephew, Aslam Khan and daily wagers were killed in the firing, while his son, Hazrat Umar sustained injuries.