MANILA, Dec 27 (AFP) - The death toll from Christmas day rains in southern Philippines has risen to 13, authorities said on Tuesday (Dec 27), with the search still on for 23 people as floods started to recede.

Most of the deaths were caused by drowning from flash floods after two days of heavy rains disrupted Christmas celebrations and forced more than 45,000 people to take shelter in evacuation centres, the disaster agency said.

Images on social media show coast guard, police and fire personnel wading through waist-deep floods and carrying residents along landslide-hit areas. Some roads were flooded by overflowing rivers nearby.

Rescue operations continued and damage to agriculture was being assessed, Carmelito Heray, head of the disaster agency in Clarin town in Misamis Occidental province, told DZBB radio station.

There was no tropical storm in the mostly Catholic nation's most important holiday. But a shear line, an area where warm and cold winds meet, caused rain clouds to form in southern Philippines.

"The big damage here is livestock because their adult pigs, chickens, goats and cows are now gone," Clarin town mayor Emeterio Roa said on radio.