Chinese President Xi Jinping on Thursday requested an immediate investigation into the cause of a stampede that broke out during a New Year Eve celebration in downtown Shanghai.

New Year celebrations in the Bund area went astray Wednesday night, when a stampede killed at least 35 people and injured 42 others.

Xi asked the Shanghai government to "go all out" to rescue and treat the injured and properly handle the aftermath.

A profound lesson should be learned from the incident, said Xi, also general secretary of the Communist Party of China Central Committee and chairman of the Central Military Commission.

Many places will hold festival gatherings and recreational activities for the upcoming Spring Festival, or the Lunar New Year, and the following Lantern Festival, he said. Xi added that local authorities should prioritize the safety of people's lives and property and make careful arrangements to ensure safety measures are in place.

Premier Li Keqiang underscored the importance of safety in public places, particularly during holidays.

Li told local authorities to "make every effort" to reduce injury-related deaths and console relatives, adding that strict precautions should be taken against major incidents, and public safety and social stability should be ensured.

The city has set up a working team for rescue operations and to deal with the aftermath.

The cause of the incident is under investigation.

A witness said that some coupons resembling U.S. dollar bills were being thrown from a building's third-floor window near the Bund, and people standing along the river bank started to scramble for them.