The Philippines said on Tuesday it would investigate whether safety regulations were ignored at an office where a fire killed 37 call center employees, and vowed to impose sanctions if firms had not met standards.

The remains of 37 employees of the U.S.-based Research Now SSI killed by Saturday's fire in Davao City have been recovered and a criminal investigation will be launched by the Justice Department.

Labour Secretary Silvestre Bello said he had instructed the government's workplace health and safety agency and the Labour Ministry's regional office in Davao, President Rodrigo Duterte's hometown, to investigate if there were lapses in safety standards.