Fifty seven of the 58 people killed in a residential building fire in downtown Shanghai on Nov. 15 have been identified, municipal authorities said Tuesday.

The names, which have been reported to authorities and investigators, would not be released to the public unless the victims' relatives agree to do so, Chen Qiwei, spokesman for the Shanghai municipal government, told a press conference.

"If the victims' families wish to release the names and obituaries, the government will give them support," Chen added.

The identity of one victim remains uncertain. Preliminary investigations show the victim could be a Japanese man. Blood samples from his relatives have been transported to Shanghai for DNA testing.

Zhang Renliang, head of Jing'an District, where the fire occurred, apologized for the tragedy.

"We've been stricken with grief since the disaster, for which we have undeniable responsibility. We feel deeply guilty," Zhang said.

The government would pay 960,000 yuan (144,450 U.S. dollars) in compensation and subsidies for each of those who died in the fire, Zhang added.

The residents whose apartments and belonging in them were destroyed in the fire will be fully compensated for their loss of property.

Shanghai Mayor Han Zheng claimed responsibility for the fire Monday.

"Poor supervision of the city's construction industry was one of the causes behind the high-rise apartment building fire. And we are responsible for that," Han said.

The blaze gutted the building, which was under renovation, on Nov. 15 after sparks from welding work set heat retention materials, nylon netting and scaffolding alight. Of the 58 people killed in the fire, 22 were men and 36 were women.

Luo Lin, head of the State Administration of Work Safety, has blamed the tragedy on unlicensed welders, illegal multi-layered sub-contracting and poor management.

Shanghai police have detained 12 people in connection with the fire.