One person was killed early Monday after an oil refinery blast rocked a settlement in the Zabaikalsky Kray in southeastern Russia, news agencies reported.

The executive director of Zabaikalsky Refining Company, Arkady Chuprov, and 18 Chinese were believed to be working at the oil refinery in the village of Dauria at around 4:25 a.m. local time (1925 GMT Sunday), when an explosion occurred inside the pumping station.

At around 12:40 local time (0340 GMT), some 30 meters from a burning oil fuel tank, a body was found, whose identity and cause of death were currently being established. More casualties could not be confirmed.

Earlier reports said five Chinese who were at the epicenter of the explosion, remained missing and were presumably thought killed. The Chinese Consulate in Irkutsk region also told Xinhua that exact information was currently being verified with the Russian side.

"The location of five of them, who happened to be in the blast center, has not been spotted yet, all of them are presumably killed," said earlier a source in the regional prosecutor's office.

The blast then caused a fire in a main warehouse with about 2,000 tons of fuel oil. The blaze cannot be localized for the moment and thus prevented investigators from inspecting the scene.

The explosion was probably caused by the use of open fire indoors, which breached the fire regulatory rules. Huge flames were seen after the blast, whose waves shattered the windows in the adjacent four residential houses some 300-500 meters away.

The pre-start operations were about to complete at the oil refinery before the blast, which destroyed some 90 percent of the installation. The project, with investment from China, aimed to bring down the automotive oil price of the remote region.

No casualties were reported in the Dauria village. Residents have been evacuated to a safe place in case of more blasts.

Firefighters and repair workers were working at the scene to put down the fire and clean up the aftermath of the explosion.

The regional prosecutor's office has launched an investigation into the incident.