By David Ljunggren
OTTAWA (Reuters) - The heaviest rain to hit the Atlantic Canadian province of Nova Scotia in more than 50 years triggered floods causing "unimaginable" damage, and four people are missing, including two children, officials said on Saturday.
The storm, which started on Friday, dumped more than 25 cm (10 inches) on some parts in just 24 hours - the same amount that usually lands in three months. The resulting floods washed away roads, weakened bridges and swamped buildings.
"We have a scary, significant situation," said Nova Scotia Premier Tim Houston, adding that at least seven bridges would have to be replaced or rebuilt.
"The property damage to homes ... is pretty unimaginable," he told a news conference. Houston said the province would be seeking significant support from the federal government.
Prime Minister Justin Trudeau told reporters in Toronto he was very concerned about the floods and promised that Ottawa "will be there" for the province.
The flooding was the latest weather-related calamity to pound Canada this year. Wildfires have already burned a record number of hectares, sending clouds of smoke into the United States. Earlier this month, heavy rains caused floods in several eastern U.S. states.
Authorities have declared a state of emergency in Halifax, the largest city in Nova Scotia, and four other regions.
The regional municipality in Halifax reported "significant damage to roads and infrastructure" and urged people to stay at home and not use their cars.
Pictures posted on social media from Halifax showed abandoned cars almost covered with flood waters and rescue workers using boats to save people.
Houston, citing police, said two children were missing after the car they were in was submerged. In another incident, a man and a youth were missing after their car drove into deep water.
At one point, more than 80,000 people were without power.
Environment Canada is predicting torrential rain in the eastern part of the province, continuing into Sunday.
"People should not assume that everything is over. This is a very dynamic situation," Halifax Mayor Mike Savage told the press conference, saying the city had been hit by "biblical proportions of rain."
Canadian Broadcasting Corp meteorologist Ryan Snoddon said the Halifax rains were the heaviest since a hurricane hit the city in 1971.
Early on Saturday, authorities in northern Nova Scotia ordered residents to evacuate amid fears that a dam near the St. Croix River system could breach. They later canceled the evacuation order.