Despite the debatable strategic success and the operational failure of the descent on Rochefort, William Pitt—who saw purpose in this type of asymmetric enterprise—prepared to continue such operations. An army was assembled under the command of Charles Spencer, 3rd Duke of Marlborough; he was aided by Lord George Sackville. The naval squadron and transports for the expedition were commanded by Richard Howe. The army landed on 5 June 1758 at Cancalle Bay, proceeded to St. Malo, and, finding that it would take prolonged siege to capture it, instead attacked the nearby port of St. Servan. It burned shipping in the harbor, roughly 80 French privateers and merchantmen, as well as four warships which were under construction. The force then re-embarked under threat of the arrival of French relief forces. An attack on Havre de Grace was called off, and the fleet sailed on to Cherbourg; the weather being bad and provisions low, that too was abandoned, and the expedition returned having damaged French privateering and provided further strategic demonstration against the French coast.
How did the invading British army do at St. Malo?
it would take prolonged siege to capture it, instead attacked the nearby port of St. Servan