China inaugurated the world's longest cross-sea bridge on Thursday as part of its effort to boost economic integration and development in the Yangtze River Delta.

Hundreds of people attended the opening ceremony for the 36-kilometer bridge spanning Hangzhou Bay near Shanghai on Thursday afternoon. It was held in the middle of the bridge.

Zhao Hongzhu, Zhejiang Province Communist Party secretary, declared the opening of the bridge at 3:40 p.m., followed by ceremonial fireworks.

Tens of thousands of local residents gathered on two banks of the bay, many of whom performed dragon dances in traditional costume to celebrate the span's opening.

The bridge will open to traffic on a trial basis at midnight.

Trucks, overloaded vehicles and vehicles that carry dangerous chemicals will be barred from passing through the bridge during the trial operation period in a bid to ensure smooth traffic and visitor safety.

"The bridge has become well-known and is expected to attract many visitors," said Jin Jianming, deputy chief commander of the bridge construction project.

"We haven't decided how long the trial operation period will last. That depends ... on the bridge condition, and we need time to improve management about its operation."