Seven people were killed Sunday after an overpass under construction collapsed in southwest China"s Yunnan Province, Xinhua quoted local officials as saying. The accident also left eight people seriously injured and 26 others with light injures. It happened at 2:20 p.m., when an overpass under construction collapsed in an uncompleted airport in Kunming, the provincial capital, said a spokesman with the municipal government. Among the 41 workers at the site, six workers were killed at the scene, while another one was found dead after his body was retrieved in the debris, the spokesman said. The collapsed section was 38 meters long and 13 meters wide, he said. With an investment of 23 billion yuan (3.37 billion U.S. dollars), the airport is designed to put through 38 million passengers every year, he said. The cause of the accident is under investigation.