As they slept in their beds retired couple Linda and Colin Walker were perilously unaware of the gang of men who were preparing to break into the next room.

Spotting a window ajar on the bungalow in Stowmarket, the men attempted to enter the property before the couple’s faithful yellow Labrador Harry, barked loudly waking up his owners.

The men are then believed to have run off as the five-year-old dog continued growling while Mr Walker got up to see what was going on.

“It was the early hours, about 3.30am when we were woken up by our dog barking quite ferociously, which is unusual for him as he’s quite laid back,” Mrs Walker, 60, said.

“Colin noticed a window was open but we did not think too much of it at the time.

“The next morning we went out into the garden and noticed there were footprints in the ground – with all the rain recently.”

Detectives were called by officers who told the couple they had been lucky as several homes in the area had been broken into with burglars entering through open windows.

The would-be criminals targeted the bungalow window, which was left on the latch, of a bathroom which joined onto the couple’s bedroom.

Mrs Walker, who worked as a psychologist before retiring, said she thought Harry, now nicknamed ‘Superstar’, had seen the men through the glass of their conservatory.

She said: “You never know what could have happened, we were really pleased that he did go berserk and woke us up.

“They came up to the back door of the conservatory and may well have tried the door but Harry was sleeping in there.

“I think he instinctively knew that it was not a good thing that there were strange men in the garden in the middle of the night.”

Now Harry, who shares the home with chocolate Labrador, George, seven, is to be featured in the magazine Dogs Today after winning a Good Boy Award for protecting his owners.

Police are appealing for information on the attempted burglary which happened on February 25.