Police have warned dog owners they could face prosecution if they do not control their animals, after a man and an eight-year-old boy were bitten by an Alsatian-type pet.
The pair were taken to hospital with minor injuries after being attacked on the Fairway Estate in Llandudno, Conwy, on Sunday at about 1500 BST.
It is thought the dog was being looked after by neighbours.
Police said the owners agreed to have the animal put down.
Inspector Ian Verburg, from North Wales Police, said: "We understand that the dog was being looked after by neighbours while the owners were away.
"We secured the animal and the owners have now agreed that their dog will be destroyed.
"It is fortunate that no one was badly injured
"I am now warning dog owners that they have a great responsibility for their animals."
He added: "Where the required care is not taken, people can be injured, as in this case, dogs destroyed and owners can face prosecution."