Three more beaches in north Dublin have been hit by another sewage pollution incident.

Fingal County Council has issued an advisory notice in respect of the beaches at Portmarnock, Howth and Sutton, which advises precautions including not swallowing water and washing hands before handling food.

Those with open cuts or who are pregnant or have a weakened immune system are asked to avoid swimming.

The council says the issue is a "short-term overflow event" from Portmarnock pump station due to heavy rainfall last night.

More serious prohibitive notices involving 'Do Not Swim' warnings had already been issued at Balbriggan, Skerries, Loughshinny and Rush.

Water samples were taken from these beaches today and results are expected by the end of next week.

Fingal Council says Irish Water is planning a €7.3 million upgrade of the Loughshinny sewage facility.