The deaths of some 90 people have been linked to cold weather which began on Oct. 18, Mexico's Health Ministry said in a statement yesterday.

The main causes were carbon monoxide poisoning, burns and hypothermia, and many of the dead were shantytown residents -- whose homes were made from wood, cardboard and corrugated iron.

The largest number of deaths, 39, occurred in the northern Mexico state of Chihuahua. Another 13 people died in neighboring Coahuila and 11 more in another northern state, Sonora.

The ministry urged residents to check heaters, stoves, pipes and chimneys for leaks and blockages.

The statement said the government was continuing its work to prevent illnesses triggered by low temperatures, mainly in the north and northeast of the country.