Qa'dah 10, 1431, Oct 18, 2010, SPA -- Surging currents sucked a bus off a flooded highway and swept away 20 of its passengers, including a girl ripped from her mother's arms, as flooding caused 30 other deaths in Vietnam and a monster Typhoon Megi loomed offshore Monday. Seventeen other people from the bus, including the driver, escaped by swimming to safety or clinging to trees or power poles, said Nguyen Hien Luong, head of Nghi Xuan district in Ha Tinh province. They were later rescued by fishermen and police, but 20 remained missing, according to a report of the Associated Press. A 46-year-old woman carrying her daughter treaded water for 3½ hours as the current dragged her 3 kilometers (1.9 miles) along the Lam River. But she was forced to let go of her daughter due to exhaustion before she was rescued. The girl was among three missing children. The bus was traveling from the central highlands province of Dak Nong to the capital when it drove through about 60 centimeters (2 feet) of gushing water and was knocked off balance around 4:30 a.m. on Monday, Luong said. Many passengers were jolted awake when the bus began to tilt sideways, state-controlled media reported.