Sky News Breaking News headline;Emergency services are mounting a major rescue operation after hundreds of people became trapped in their workplaces by rising flood waters in Sheffield. People stranded inside buildings told Sky News how they had watched helplessly as walls were pulled down and cars swept away by torrents of water raging outside. Police said 25 people were trapped inside their cars on Brightside Lane. The RAF has scrambled helicopters to winch people to safety after being deluged with calls for help from the Brightside area. Michael Mulford, of RAF Kinloss, told Sky News it was difficult to tell which call to respond to first. "We're getting reports of people hanging out of windows, reports of buildings that are already down or on the verge of collapse," he said. Sheffield Police have advised people not to try to escape through the waters and to wait for the emergency services to reach them. Sky News correspondent Miuke McCarthy said the water was still rising in the city even though the rain has eased off.