A sailor had to be rescued after his boat began to sink in heavy swells off the north shore yesterday.Marine police were called out just after 2pm after the solo mariner got into distress about 200 metres from the shore off Grace Church, Pembroke.A police spokesman said: “Upon arrival it was confirmed that the 20ft vessel was approximately 200 metres from the shore and the operator of the vessel was clearly in distress due to heavy swells in the area and the vessel began to sink.“The boat was secured and then assisted to Devonshire Dock by marine police The lone person on board the vessel was unharmed.”