Rescuers are racing to free hundreds of workers believed to be trapped in tunnels at hydropower sites that were buried in mud by catastrophic flooding on the Nepal-China border. The efforts unfolded Monday as the death toll climbed and increasingly desperate families searched for missing loved ones. The combined deaths in Nepal and China surpassed 950, with more than 4,400 people missing. A private-sector association representing power companies says at least 900 workers are unaccounted for at 12 damaged hydropower projects. About 500 of those workers were believed to be trapped in tunnels.