Laura Behjet was walking tiny chihuahua Charles and her other dog in Shenley Brook End on Sunday when she noticed two loose border terriers in the distance.
At that point little Charles, who weighs less than 5lb, slipped his harness and ran off towards hedges at Garthwaite Pavilion.
"He ran far away from the approaching dogs, but the two terriers chased after him," said Laura.
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“Me and my children started running down to get him back… We could hear screams but we couldn’t see anything because of the hedge.”
The children got to the scene first and to their horror they saw the two terriers shaking and pulling little Charles between them.
By the time Laura caught up, the terriers were restrained on leads and their owner had picked up the little chihuahua, who was covered in blood.
"My children were hysterical… The woman handed Charles to me and kept saying ‘he’ll bite you’ – even though he’s never shown aggression.
"When it became clear he was covered in blood, she laughed and said it was her blood because he had bitten her.
"She didn’t at any point seem shocked. She spoke very calmly to me and my children saying things like ‘it’s okay he’s not injured, it’s my blood’.”
In fact, the chihuahua had been very seriously injured and both his lungs has been punctured by the dogs’ teeth.
Laura asked another nearby dog walker what had happened and he said the terriers had chased Charles and repeatedly bitten him.
"He said he had to kick them to get them off,” she said.
As they spoke, the two terriers were pulling on the lead, trying to get to Charles again.
“At no point did the woman offer any details and eventually I just said ‘I have to get him to a vet’ and walked off,” said Laura.
“When we reached the vets’, they said the dogs had crushed his chest… We were warned the bill could exceed £15,000 and he may die at any moment.”
Charles’ X-rays showed collapsed lungs where the dogs had bitten right through his body.
The surgery took four hours, and the chihuahua’s chest was so badly damaged that the vets had to use some of his ribs to reconstruct it.
“By some miracle Charles has survived and will hopefully be able to come home soon,” said Laura. “We don’t know if there will be lasting physical problems as a result of his injuries.”
Laura has reported the incident to police and has walked miles going door to door and asking other dog walkers if they know of the two border terriers.
"I have people I have spoken to who have given statements to the police because these same two border terrier dogs have attacked their dogs,” she said.
"We are aware of two, possibly three other attacks.
“it is even important to find the owner as the dogs are unmuzzled and sometimes off leash.”
Meanwhile, little Charles is recovering slowly.
Laura said: “We imagine there certainly will be significant psychological damage as he is a shy, gentle little dog. We think he will now be absolutely terrified of other dogs.”