CHANGCHUN, Feb. 28 (Xinhua) -- Heavy snow hit northeast China on Wednesday, causing flight delays and expressway shutdowns.

As of 5:30 p.m., all sections of expressway in northeast China's Jilin Province were shut down due to snow, according to local expressway authorities.

The airport in Changchun, capital of Jilin, was closed. More than 100 inbound and outbound flights were delayed, and some 20 inbound flights have been diverted to other airports.

Rescue workers have been dispatched to clean snow and ice from roads and at railway stations.

The National Meteorological Center has issued a yellow alert for snowstorms for Wednesday and Thursday in northeast China, including Heilongjiang, Jilin and Liaoning provinces. Some areas are expected to see blizzards.

In the country's four-tier weather warning system, red is the most severe, followed by orange, yellow and blue.