The frozen section of the Yellow River estuary has expanded to nearly 600 kilometers on Monday as temperatures continued to plummet in Shandong Province.

The ice density in the main part of the river was 10 percent to 30 percent, with the largest piece of ice estimated at about 150 square meters, said Chen Xianjun with the Yellow River Shandong Bureau.

Temperatures plunged last week in the eastern province and are expected to remain low this week. Monday's low was recorded at 8 degrees Celsius.

"If the frozen area continues to expand, the river is likely to be blocked," Chen said.

Local governments are removing float bridges across the river in the region to ensure a smooth ice flow.

The annual ice run was first spotted at the outlet of the Yellow River on Dec. 31, about half a month later than usual. Ice formations at the lower reaches of the river usually last to February. River freezing can pose a hazard to the safety of embankments along some narrow and winding sections, where a large amount of ice always accumulates.

The Yellow River, the second longest in China, originates in Qinghai Province in the northwest and flows through Gansu, Ningxia, Inner Mongolia, Shaanxi, Shanxi and Henan, before emptying into the Bohai Sea.

(Xinhua News Agency January 14, 2008)