Manila: Rescue workers were sifting through mud and debris from the ruins of a government building in the Philippines on Monday, a day after it collapsed during the onslaught of a typhoon.

The mayor of the town of Natonin in Mountain Province, Mateo Chiyawan, said at least three bodies had been recovered from the building collapse, while dozens more people were feared dead after a mudslide hit the structure.

The two-storey building, in Sitio Sakrang, collapsed at around 4pm on Tuesday as Typhoon Yutu unleashed 140km/h winds and heavy rainfall, reports quoted engineer Jonel Emengga, head of the Department of Public Works and Highways (DPWH) in Mountain Province, as saying.

“The landslide brought down a big volume of mud, leaving no traces of the DPWH compound,” Emengga said.

He added that the DPWH had ordered that the building be vacated hours before the typhoon arrived.

Only two private security guards were supposed to be on the premises.

However, people from nearby houses had sought shelter in the building when disaster struck.

“The building is beside a residential area and the strong rain and wind could have prompted residents to seek refuge at the [concrete] office,” Emengga was quoted as saying by the state-run Philippine News Agency.

He added that the guard on duty at the time, who had kept track of the number of people in the building, was among the missing and there was no way they could determine how many people were inside the structure when it collapsed.

Photos of the collapsed building showed how the mudslide flattened the structure.

Yutu, referred to in the Philippines as typhoon “Rosita” arrived over the Quirino and Isabela regions before noon on Monday with weather authorities placing these areas under warning signal 3.

Warning signal No. 2 was in place over the provinces of Cagayan, Nueva Vizcaya, Aurora, Ifugao, Nueva Vizcaya, Benguet and La Union.

Yutu exited the Philippine Area of Responsibility on Tuesday afternoon, according to the state weather bureau, PAGASA.

The Mountain Province was hit hard by the effects of Yutu. Aside from the fatalities from the collapsed building, other deaths were reported in the village of Batad in Banaua, Ifugao where a family of four were killed in a landslide.

A five-year-old child was also reported to have died from a similar incident in the village of Mabilog Lubuangan in Kalinga.

Officials said they were still in the process of assessing casualties caused by the typhoon.

In a statement, presidential spokesperson and chief presidential legal counsel Salvador Panelo said the palace expressed its deep condolences to the families and loved ones of the victims who perished in Natonin, Mountain Province.

“Efforts to look for survivors are currently ongoing and we pray for the rescue of those still trapped or missing,” he said.

The National Disaster Risk Reduction and Management Council (NDRRMC) said that as of 6am on Tuesday, a total of 11,878 families, or 38,398 persons, were affected in 478 villages in the Ilocos, Cagayan Valley, Central Luzon and the Cordillera Autonomous Region.

More than 10 landslide incidents were reported in the area.

Earlier, similar incidents had prompted President Rodrigo Duterte to declare a moratorium on smalls scale mining activities in certain provinces.