At least 35 people were killed and hundreds trapped after flash floods swept through a valley in Pakistan's north-western region of Khyber-Pakhtunkhwa early Thursday, government officials said. The floods, brought about by heavy overnight rain, washed away dozens of houses in the Gabriyal area of the remote mountainous district of Kohistan, and left some 30 more people missing, dpa reported. "The rescue workers assisted by local residents have recovered 35 bodies so far," said Imtiaz Hussain Shah, the civilian head of the district. "We are looking for between 25 and 30 more people which are believed to be missing." "It's a remote and difficult area and the rescue teams are trying to reach Karang village through mountain treks," Shamsur Rehman, a local police official said. "The village is surrounded by the water and has turned into an island." Shah said that the Pakistan Army had provided two helicopters to reach the for the relief activities in the area but they would start operating from Friday. The district was also hit hard during last year's floods, which inundated almost one fifth of Pakistan's land, displaced 18 million people and killed more than 2,000.