Ten French fishermen were rescued when their trawlers began to sink in a Devon harbour.
The Sagitaire and the Saint Christophe were rescued in the early hours at Town Quay, Dartmouth, where they had taken refuge from storms.
An anti-pollution boom has been put around the Saint Christophe amid fears that more than 10,000 litres of diesel could escape.
Dart inshore lifeboat rescued five crew of the Sagitaire over the stern.
Devon and Somerset Fire and Rescue Service rescued the five crew of the Saint Christophe by ladder.
Emergency services received the call just after 00:35 GMT on Thursday and found the vessels were listing and aground.
The lifeboat crew found severe internal flooding on the Saint Christophe.
A boom was placed round the vessel by the Dart Harbour Authority vessel, Hercules, to prevent an oil spill.
Harbour master Captain Rob Giles said there were 10-15,000 litres of diesel oil on board, but only five litres had escaped so far.
"Our primary concern is to safeguard the area," he said.
The fire service sent two appliances from Dartmouth, one from Kingsbridge, one from Paignton, and a pump and command unit from Totnes.