At least 325 people were killed and hundreds remain missing in the Philippines following the deadliest typhoon to hit the country this year, the civil defense chief said Thursday.

"We have 325 dead and this is expected to rise because many more are missing," civil defense chief Benito Ramos told a news conference.

He did not give a fresh total for the number of missing after Typhoon Bopha ravaged the southern island of Mindanao on Tuesday.

However he noted that both figures were "rising rapidly from single- to triple-digits" as rescuers reach more remote areas.

Shortly before the latest announcement, Ramos' office, the National Disaster Risk Reduction and Management Council, had put out a tally listing 322 dead and 328 missing.

"Communications are bogged down, there is no electricity, roads and bridges have been destroyed," Ramos said.

"We're still on a search-and-rescue mode," he added.

Ramos meanwhile warned seafarers to exercise caution even though Bopha blew out to the South China Sea overnight Wednesday.

"It does not mean that our waters are safe now," he said. (AFP)