AlQa'dah 5, 1434, Sep 11, 2013, SPA -- Suspected separatists on Wednesday shot dead five plainclothes policemen who were investigating oil smuggling in Thailand's violence-wracked southern provinces, officials said, according to DPA. "The suspects opened fire on the policemen while they were in a pickup truck," Internal Security Operations Command spokesman Colonel Pramote Prom-in said. "When the truck stopped, the suspects pulled them out and finished them off, taking their guns and mobile phones," he said. The incident occurred at 10:40 am (0340 GMT) in Tung Yang Daeng district of Pattani, 770 kilometres south of Bangkok.