Ice storms are continuing to batter central and eastern US states and the death toll have risen to 36, CNN reported Monday.

Since last Friday, waves of freezing rain, sleet and snow have so far caused at least 15 deaths in Oklahoma, eight in Missouri, five in Iowa, four in New York, three in Texas, and one in Maine, according to the report.

The extreme weather downed trees, traffic lights and power lines and blocked roads in Missouri and Oklahoma.

US President George W. Bush has issued disaster declarations for Oklahoma so it can receive federal assistance.

The Missouri state government has declared a state of emergency and called up the National Guard troops after the storms knocked out power to 200,000 homes there.

The National Weather Service said the storm system is heading north-east, threatening to bring more than 30cm of snow to New England.

Ice storms occur when rain falls during very low temperatures, causing it to freeze almost instantly as it hits a surface, resulting in thick ice layers.

In Texas, 415 flights were canceled on Sunday at Dallas-Fort Worth International Airport.

Record-breaking cold weather even hit California, which usually has mild temperatures year-round.

Citrus fruit growers in parts of the state are using wind machines to protect their fruit from frost damage.

At present, the storm is gathering moisture from the Gulf of Mexico and cold air from the Arctic, and is expected to hit US east coast on Tuesday.

(Xinhua News Agency January 16, 2007)