MANILA (REUTERS) - The Philippines has suspended operations of a shopping mall and a call centre run by a US firm where a fire killed 38 people, citing failure to fully comply with fire safety requirements for five successive years.

Investigators looking into the Dec 23 blaze in Davao City, which broke out at a furniture and fabric store on a lower floor before engulfing the call centre's offices, said there were indications of fire safety lapses that might have contributed to the tragedy.

Charito Plaza, director-general of the government's Philippine Economic Zone Authority (PEZA), said the agency has suspended the registration of the New City Commercial Center (NCCC) and American firm Research Now SSI in Davao for failing to meet certain safety requirements since 2013.

"Violations were more of the non-compliance of annual emergency drills to test the fire safety equipment, response and rescue capability, sprinklers and emergency exits," Plaza told Reuters in a text message.

The suspension took effect on Dec 29, which meant NCC and SSI will be barred from any further expansion in the Philippines.

NCCC could not immediately be reached for comment. An SSI official declined to comment and referred Reuters to its legal representative.

SSI employed 500 people at the Davao call centre and since the fire said it would not comment until after investigations were concluded. NCCC has insisted it had met safety requirements.

Four fire officials being questioned over the blaze have been relieved of their duties after initial findings from a probe showed they have "some liabilities" a government investigator said on Monday.