Iraqi security forces backed by Sunni tribes battled al-Qaida militants Sunday in Anbar as hundreds of families left their homes in the restive western province, police source and officials said. Armored vehicles and tanks backed by helicopters continued their battles for the fourth day with al-Qaida militants at the town of Khaldiyah, some 30 km east of Ramadi, the provincial capital, a police source told Xinhua. "The troops fought the terrorists on the edge of Khaldiyah and the nearby open land area (locally named al-Jazira)..., and the clashes resulted in the killing of three gunmen and the wounding of two others," the source. Separately, a soldiers was killed and three others were wounded in a clash that occurred around noon between the army and al-Qaida militants in al-Girtan area near Khaldiyah, the source added. Meanwhile, Ali al-Rawi, an official in Anbar's provincial council, told reporters that some 1,000 families have left their homes in the town of Khaldiyah and the nearby areas, fleeing to other cities. "Nearly 1,000 families, most of them are women, children and elderly, have left their homes in Khaldiyah Jazira to the cities of Heet, Rawa and Aanah, because of the clashes and the shelling on their homes," Rawi said, adding that many of the remaining families are locked in their homes by the clashes. Anbar province has been the scene of fierce clashes since police dismantled an anti-government protest site outside Ramadi in late December. The Sunnis have been carrying out a year-long protest, accusing the Shiite-led government of marginalizing them and its Shiite- dominated security forces of indiscriminately arresting, torturing and killing their sons. On Wednesday, the UN warned that the humanitarian situation is critical in the province.