ZURICH, (Reuters) - Between 10,000 and 15,000 litres of heating oil spilt into the River Rhine on Friday after an accident in the river harbour of Kleinhueningen near Basel, Basel police said.

An international Rhine alarm was issued as the river flows through Germany, France and the Netherlands before reaching the North Sea.

Police said the accident occurred at about 1200 GMT while the Dutch-registered barge Discovery was pumping oil into a tank beside the river. A Belgian cargo ship passed too close to the river bank, creating a big wave which pushed the Discovery a few metres away and ruptured the pipeline used for the oil transfer.

The Basel fire brigade is trying to contain the spill and remove the oil, police said.