NANJING, Sept. 19 (Xinhua) -- China has mobilized more than 20,000 military troops and reservists to help local people fight typhoon Wipha by reinforcing flood barriers along the main rivers.

On receiving the typhoon alarm, troops from the People's Liberation Army and Armed Police Forces garrisoned in east China's Zhejiang and Fujian Provinces were called into action.

Wipha hit Cangnan County in Zhejiang Province at 2:30 a.m. on Wednesday, destroying 669 houses, disrupting power supplies to 1,867 villages, affecting about five million people and resulting in direct economic losses of 2.9 billion yuan (38 million U.S. dollars).

The troops oversaw the evacuation of nearly 100,000 people.

Wipha weakened to tropical storm at about 11 a.m., with wind speeds at its eye measuring 83 kilometers per hour, and moved northwestward, approaching the commercial hub of Shanghai.