Police in Dalian, Liaoning province, have detained five people they say are responsible for damage to a crude-oil pipeline that triggered a massive oil leak and fire on Monday night.

The five were responsible for a drilling operation that damaged the pipeline near Dalian University in the city's Jinzhou New District, the Dalian emergency office said.

No casualties were sustained in the incident, but residents living nearby had to be evacuated and all the city's fire engines were mobilized, according to Ministry of Public Security's fire department, the nation's leading firefighting agency.