Traffic on the River Rhine has resumed after an oil spillage near the Swiss city of Basel over the weekend.
The authorities said clean-up operations would be completed by Tuesday.
The accident occurred on Saturday near the port of Birsfelden outside Basel, when more than 100kg of heavy heating oil spilled into the river, apparently while it was being pumped into a German freighter.
Emergency services set up dams to prevent any further spillage and the river had to be closed off to traffic between Birsfelden and Basel.
Officials said two people were injured in the accident.
But they said it was not clear yet how much damage the oil spillage had caused.
However, the authorities described clean-up efforts as very important.
The Birsfelden terminal is one of four ports in Basel, which links landlocked Switzerland with Rotterdam on the North Sea.
The Rhine ports of Basel handle about nine million tons annually. This amounts to 15 per cent of Switzerland’s foreign trade.
swissinfo with agencies
Basel’s Birsfelden port specialises in warehousing and trans-shipping liquid fuels and dry cargoes.
The biggest port is in Basel Kleinhüningen, while St Johann is the oldest port.
The port of Au-Muttenz specialises is the handling of heavy-lift cargoes.
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