A Chinese court has agreed to hear a lawsuit brought against US firm ConocoPhillips by a group of fishermen over an oil spill, state media said Friday.

The June leak released more than 3,000 barrels of oil and oil-based mud -- used as a lubricant in drilling -- off China's northeastern coast, drawing widespread public criticism and warnings from Chinese authorities.

Lawyers for a group of 29 fishermen filed a case with the Tianjin Maritime Court in northern China, claiming the leak from a field operated by ConocoPhillips killed many of their clams and sea cucumbers, a form of seafood.

The official Xinhua news agency said Friday the court had accepted the fishermen's suit, but gave no details on the amount of compensation being sought.

Calls to the court, ConocoPhillips and to the fishermen's lawyer went unanswered.

Xinhua also reported that the same court was checking the identities of 107 fishermen who have filed a separate case against ConocoPhillips seeking 490 million yuan ($78 million).

It said that case had been rejected on December 13 and the court asked those fishermen's lawyers to refile with more evidence.

The spill, which happened near platforms jointly owned by Conoco and Chinese state-owned giant CNOOC, polluted over 6,200 square kilometres of water in Bohai Bay, the report said -- more than eight times the size of Singapore.

Houston-based ConocoPhillips agreed in September to comply with a Chinese order to halt production at the platforms where the spill occurred and set up compensation funds in recognition of its responsibility for the accident.

It was not immediately clear if production has since resumed.

A separate lawsuit connected to the spill has been filed in the eastern city of Qingdao by more than 200 fishermen seeking 30 million yuan in compensation, but it was unclear whether the court there has accepted the case.

The State Oceanic Administration -- the government agency that supervises and manages China's seas -- has also said it will sue ConocoPhillips over the leak.

Environmental groups and local fishermen have accused ConocoPhillips and CNOOC of initially covering up the spill, saying it was discovered in June but only made public nearly a month later.

Both firms deny the allegations. ConocoPhillips says it cooperated with authorities as soon as the accident occurred.