HUIZHOU, Guangdong - A fire that broke out early on Monday at an oil refinery in South China's Guangdong province did not threaten the safety of the nearby Dayawan Nuclear Power Station, local authorities have said.

Smoke volume emits from the Huizhou Refinery operated by the China National Offshore Oil Corp in Huizhou, Guangdong provinceon July 11, 2011. [Photo/CFP]

The fire was reported at 4:10 am after oil ignited after leaking from equipment at the Huizhou Refinery run by China National Offshore Oil Corp (CNOOC), said a spokesman from the Dayawan Economic and Technical Development Zone.

Flames rose to more than 100 meters and 63 fire engines were used to fight the fire, the spokesman said.

No casualties were reported.

As of 5:20 pm, the fire had been extinguished, according to sources with the Guangdong provincial fire control authorities.

However, worries about further incidents related to the fire were raised among netizens, given that the refinery is only 40 km from the Dayawan Nuclear Power Station, which is one of the major nuclear installations on Guangdong's coast.

"I thought of the nuclear power plant when the fire was reported. It could have been so dangerous," said YanyanV, a netizen who was commenting via weibo.com.

Pictures posted online appeared to show people who live near Dayawan Bay fleeing the area after the fire was reported.

However, the fire control authorities said any concerns about the blaze impacting the nuclear power plant were groundless.

Firefighters battle a blaze at the Huizhou Refinery operated by the China National Offshore Oil Corp in Huizhou, Guangdong province, on Monday. Chen Yubin / for China Daily

"The fire is under control. The fire-fighting materials used have been collected and transferred to an oil spill containment pool. There is no need to worry about further incidents," Gao Gang, a spokesman from the Guangdong provincial fire control authority, told China Daily.

Representatives from the Ministry of Environmental Protection stationed within Dayawan Nuclear Power Station also said the fire would not affect the facility.

As of 2 pm on Monday, the fire had been contained to an area of about 10 square meters, sources from the fire control authority said.

Firefighters continued to fight the remaining flames and were mindful of a large quantity of materials at the site, including 1,170 tons of dimethylbenzene, an inflammable chemical.

"We kept the flames within a controllable area," Gao said.

Firefighters also directed water toward other equipment to keep it cool and prevent the risk of explosions.

As of 3 pm, the levels of carbon oxides and inhalable particles at the refinery were all within safety limits, according to the police authority within the Dayawan Economic and Technical Development Zone.

CNOOC sources said on Monday morning that the fire did not cause any toxic spills and noted that only carbon dioxide had been detected among the smoke.

The local environmental protection authorities have set up eight monitoring stations near the refinery to keep a watch out for pollution.

Firefighters also installed an embankment near the fire to ensure oil could not leak into the sea.

An official from the city's environmental protection bureau said the fire did spew a lot of soot into the air.

"And at some monitoring stations, we observed a 60-percent increase in the levels of carbon monoxide," he added.

The pollution, however, would not seriously affect residents, the official insisted.

Diao Guotao, Party chief of the CNOOC Huizhou Refinery, said the fire will not affect the company's production targets this year.

"So far, we don't know if it was caused by human error or a mechanical breakdown," Diao said, noting that the investigation will continue.

The fire next to Dayawan Bay follows on from an oil leak that affected more than 840 square kilometers of Bohai Bay, in Northeast China, in June.

The Penglai 19-3 oilfield in Bohai Bay is a cooperative project between the Hong Kong-listed CNOOC, China's biggest offshore oil producer by capacity, and US energy giant ConocoPhillips.