The strongest typhoon to hit the Philippines in years killed at least 10 people as it generated waves as big as houses and destroyed swathes of vital rice crops, authorities said on Tuesday.
Many areas in the north of the Philippines' main island of Luzon remained without power and communications facilities, a day after Super Typhoon Megi ripped over the region with wind gusts of 260 kilometres (161 miles) an hour.
The strong winds had subsided by Tuesday as Megi headed out to sea and towards China, although heavy rains continued to fall across large parts of Luzon for a second straight day.
Rescuers were also struggling to reach isolated areas, particularly in the heavily hit coastal communities of Isabela province that bore the brunt of the typhoon, officials said.
"The waves in Maconacon were as big as houses and swamped the town plaza facing the Pacific Ocean," Isabela governor Faustino Dy said over DZBB radio as he appealed for help.
Dy said water, food and medicine were desperately needed in Maconacon, a village of about 4,000 people that remained isolated and only accessible by helicopter or by small boat.
Three people in Maconacon drowned in the storm surge and many others were wounded on Monday, he said.
Dy said he could not give a full report of the damage to all coastal areas because the 240-kilometre northeastern shoreline of Isabela remained difficult to reach.
But he said nearly 100,000 hectares (247,000 acres) of rice and corn crops had been destroyed across Isabela, one of the Philippines' key farming regions.
Elsewhere in Luzon, four people were reported killed in Pagansinan province, three of them by a collapsed structure and the other by lightning, the Red Cross said.
The National Disaster Risk Reduction and Management Council in Manila had earlier reported three people killed elsewhere in Luzon.
However, after thousands of people had been evacuated well before Megi struck as part of intense preparations that involved the military, there were hopes the death toll would not climb substantially.
The northern parts of Luzon are mostly agricultural and fishing areas, with a few million residents who are well-drilled in preparing for the many storms that hit each year.
"We are hoping that the casualties remain low," Red Cross secretary general Gwen Pang told AFP.
"We can't say it will not go up, but people were more prepared this time.
"What we are expecting is more reports of heavy damage. There are still many areas without power and communications, while some roads are cut off by landslides."
About 7,900 people in the northern regions of Luzon remained in evacuation centres on Tuesday, the government said, and many areas remained inaccessible because of debris littering the roads.
Megi exited the Philippines' western coast at midnight (1600 GMT) on Monday, and on Tuesday morning was heading towards Hong Kong and China with wind gusts of up to 195 kilometres an hour, according to the Philippine weather bureau.
Preparing for the storm, China issued a national early disaster warning for regions along the southern coast -- Fujian, Guangdong, Guangxi and Hainan.
Hainan island had already been hard-hit by heavy rains in recent weeks.
Authorities called on officials in the Chinese provinces to ensure that people in low-lying areas are evacuated early.
Manila's state weather bureau said Megi was the strongest typhoon since Typhoon Durian triggered deadly mudslides in the Philippines' eastern Bicol region in 2006, killing over 1,000 people.
The Philippines is hit with an average of 20 typhoons a year.