Around 1,100 people have been killed by flash flooding in Pakistan and dozens more are missing, government officials said on Sunday, according to dpa. Rescue workers struggled to reach some 27,000 people stranded by the havoc wrecked by the flooding triggered by heavy monsoon season, mostly in the north-western province of Khyber-Pakhtunkhwa. UN officials said many in the areas affected by the worst flooding in the country in decades were taking refuge on ridges or rooftops. Roads and bridges have been washed away by the flood waters, making it difficult for rescue workers to reach those who need help. Entire villages and millions of hectares of farmland were inundated in Khyber Pakhtunkhwa, which has been the worst-hit with over 1000 deaths, according to the provincial Information Minister Mian Iftikhar Husain. The flood water has also swept away tens of thousands of acres of crops, government buildings, businesses, schools, and homes. Even though the water had started to recede in the affected areas, the national Meteorological Department said that the various parts of the country were expected to receive another spell of the monsoon rains within the next 24 hours. The met office has predicted a 10 percent more rain this year than usual in these months of the year. This could not only hamper the ongoing rescue and relief efforts but worsen the disaster. Over 1.1 million people have been affected by the waters, according to the United Nations Office for the Coordination of Humanitarian Affairs (UNOCHA). "We have 27,337 people stranded at various places and rescuers are trying to evacuate them," UNOCHA official Nicki Bennett said. The UN would need donors help to re-stock its stores to maintain regular humanitarian supplies, she said. President Asif Ali Zardari said all available resources would be used to help those stranded by the current floods. Pakistan has mobilized more than 30,000 troops for relief efforts. An army spokesman said Sunday that troops had evacuated more than 19,000 people in different areas by using helicopters and boats. Refugees were crowded in schools and other official buildings, located at the higher grounds, without adequate food and fresh water. "We were about to drown when we left everything, just picked the children and came to this building, but we are not getting enough to eat," said one victim near Peshawar, the capital of Khyber Pakhtunkhwa. Faisal Naizi, from the Mianwali district in the eastern province of Punjab, said many rural areas were completely submerged. "Thousands of people are trapped in these areas and looking for assistance," he said. The European Commission is providing 39-million-dollar assistance to help the people hit by the flooding. The United States has promised to help the flood-stricken people by supplying at least 50,000 meals, helicopters, rescue boats and water filtration units, a statement from the American embassy said on Sunday. Torrential rains have also hit Pakistan-administered Kashmir region, resulting in over 57 deaths and more than a dozen deaths in central province of Punjab. Pakistan like other South Asian countries experiences an annual monsoon, which brings heavy rains to the whole subcontinent in July and early August.