Thirteen other Thai troops were injured , Lt. Col. Siriya Khuangsirikul said . NEW : Authorities evacuate at least 7,000 people as clashes erupt . Two Thai troops are injured and two are killed , the military says . A Thai military spokesman says the cause of the fighting is unknown . The fighting began more than two weeks after clashes in another disputed border area .
NEW : Authorities evacuate at least 7,000 people as clashes erupt . Two Thai troops are injured and two are killed , the military says . A Thai military spokesman says the cause of the fighting is unknown . The fighting began more than two weeks after clashes in another disputed border area .