Beijing - Seventeen people have been killed in a coal mine blast in northern China, the government said Saturday, in the second major industrial accident to hit the country this week.

The early morning explosion destroyed more than 10 dormitories at the Liugou coal mine near Linfen city in the northern province of Shanxi, the State Administration of Work Safety said on its website.

Seventeen people were killed and another 68 were injured - seven of them seriously - in the blast, the administration said. The injured were taken to hospital for treatment.

A local coal mine safety official told AFP that 60 workers had been slightly hurt in the explosion, with six suffering serious injuries.

Local authorities were continuing rescue efforts to reach any workers who may be still trapped inside the sleeping quarters, the work safety bureau said.

It was not known how many miners were inside at the time of the blast, another local official told AFP, adding that an investigation into the cause of the accident was under way.

The official Xinhua news agency said preliminary findings showed the blast may have been caused by explosives illegally stored in a dormitory and that a suspect had been detained by police, who have launched an investigation.

AFP's calls to the coal mine's owners, Yangquan Coal Industry (Group) Co. Ltd, went unanswered.

But a senior official at Yangquan Coal Industry told Xinhua that the number of dead and injured could rise further.

On Wednesday, 13 people were killed by a powerful chemical pipeline explosion that rocked a city in eastern China.

More than 300 others were injured in the blast, which occurred on the grounds of an abandoned plastics factory in Nanjing, capital of Jiangsu province, as workers were demolishing the facility.

China's vast coal mining industry is notoriously accident-prone due to lax regulation, corruption and inefficiency as mines rush to meet soaring demand.

China relies on coal-generated power for about 70 percent of its electricity needs.

A total of 2,631 miners were killed in China last year, according to official figures, but independent labour groups say the actual figure could be much higher as many accidents are covered up to avoid costly mine shutdowns.

In other accidents this month, 13 workers were killed in a flooded coal mine in the northwestern Gansu province.

In a separate incident, police detained a coal mine owner after 28 workers died in a blaze at his colliery in Shaanxi province, in the country's northwest.

The workers died after electrical cables caught fire on July 17 at the Xiaonangou coal mine in Hancheng city.

In March, a flood at the huge, unfinished Wangjialing mine in the industry's northern heartland of Shanxi left 153 workers trapped underground. A total of 115 were recovered alive, in what was seen as a rare successful rescue.

Despite numerous pledges after that accident and other big mining disasters, there is virtually no let-up in the regular reports of deadly mishaps.

Zhao Tiechui, head of the State Administration of Coal Mine Safety, said in February that China would need at least 10 years to "fundamentally improve" safety and reduce the frequency of disasters.

As part of efforts to increase safety standards, the central government has levied heavy fines and implemented region-wide mining shut-downs following serious accidents. - Sapa-AFP