About 40 workers are trapped inside a tunnel after the under construction structure collapsed in Uttarakhand yesterday, prompting the authorities to launch a mega search and rescue operation. Rescue workers said that the workers trapped for over 24 are safe and a communication has been established with them. Officials say they are hopeful of rescuing the workers by this evening. Two water pipelines are being used by the officials for food and oxygen supply. "They have been sent food items through one pipeline, and additional oxygen is being supplied to them through the second pipeline," officials said.