A man who won the Victoria Cross (VC) for leading a daring naval raid during World War One is to be commemorated on the centenary of the event.

Lt Richard Sandford, from Exmouth, Devon, blew up his submarine at the entrance to Zeebrugge port in 1918, in order to block German U-boats.

After the raid he and his crew escaped in a rowing boat before being rescued.

The flagstone honouring his heroics will be laid in his hometown during a dedication service later.

Lt Sandford's operation was part of the Zeebrugge Raid on 22 and 23 April 1918, which was an attempt by the Royal Navy to block off the Belgian port to German vessels and therefore keep them out of the English Channel.

Aged 26, he was a lieutenant commanding an HM Submarine C3 - one of two old submarines filled with explosives were to be used to blow up the viaduct connecting the mole - a large solid structure serving as a pier - to the shore.

As part of the same operation, 200 Royal Marines were to be landed in an attempt to destroy German gun positions.

However, the first submarine did not make it to Belgium in time and the marines suffered heavy casualties after coming under fire.

Lt Sandford's VC citation revealed he managed to place his submarine beneath the viaduct which connected the mole with the shore, before laying his fuse and abandoning ship.

The Victoria Cross dedication service is part of the World War One centenary commemoration campaign to honour VC recipients.

Members of Lt Sandford's family will attend the ceremony, led by United States Navy Chaplain the Rev Mike Beasley.

His VC, which is displayed at the Britannia Royal Naval College, Dartmouth, was one of 628 handed out during and after World War One.