VANCOUVER, CANADA - An explosion that damaged a natural gas pipeline in northeast British Columbia this week is likely linked to earlier attacks on energy facilities in the area, Canadian police said on Thursday.

The leak at a facility in Pouce Coupe, British Columbia, was discovered early on Wednesday when EnCana Corp workers noticed a drop in pipeline pressure, according to the Royal Canadian Mounted Police.

'This blast is considered the fifth in a series of criminally motivated acts that have occurred at EnCana sites in northeastern British Columbia spanning 2008 and into 2009,' police said in statement.

Investigators from the RCMP's anti-terrorism unit were part of the investigation.

EnCana crews were trying to stabilize the leak so police can conduct a more detailed investigation, but the leak posed no danger to the public, officials said.

'If this was set deliberately it's very frustrating for us. Fortunately no one was hurt,' EnCana spokeswoman Rhona DelFrari said.

The four earlier explosions damaged EnCana-owned pipeline facilities near the communities of Dawson Creek and Tomslake between October and January, and investigators believe they were linked to a letter warning EnCana to leave the area.

Pouce Coupe is a rural community just south of Dawson Creek and not far from British Columbia's border with Alberta.

None of the earlier explosions caused injuries, but at least two of them caused small leaks. EnCana said it was unclear how much gas had leaked because of the most recent incident.

Police have said the person responsible for the bombings probably lives in the area, and have complained that some residents who may have information about the attacks have refused to cooperate with investigators.

Threatening letters sent to media in the Dawson Creek area complained about the production of 'crazy' natural gas, a possible reference to deadly sour gas that is produced in the area and shipped by EnCana.

The facility involved in the most recent explosion did not carry sour gas.