A pipeline leak has cut water supplies to thousands of families for more than 18 hours in the northeast China city of Changchun, local authorities said Wednesday.

The leak occurred at 10 a.m. Tuesday, but the Changchun Water Group did not halt water supply immediately for fear of disruption, especially during peak hours in the evening, a company spokesman said.

About a fifth of the city has seen water cuts since 8 p.m. Tuesday when workers began fixing the broken pipeline, the spokesman said.

"The water supply is expected to be back to normal at about 6 p.m. today," he said.

He did not reveal the cause of the leakage.

Changchun, a city of almost 5 million people, is experiencing cold winter weather, and most of the heating supply companies have been using reserve water provide heating after the water supply was cut.

"But in a few areas, heating was suspended," said a spokesman with the Changchun Municipal Heating Supply Office.