SEATTLE - A Wallingford family's dog died Thursday morning following emergency surgery after someone shot it with a razor-tipped hunting arrow.

Now the Humane Society is offering a $2,500 reward for information leading to the conviction of the person who did it.

The gruesome story unfolded after the family opened their back door on Wednesday.

They discovered that someone had shot their 7-year-old mastiff Conan with the arrow and left it for dead.The O'Haras were taking their daughter to a babysitter when they found their beloved dog sitting in a puddle of blood.

"She was the one who first saw him and said 'Conan has an arrow in him,'" said Kevin O'Hara, the dog owner's father.

The arrow had sliced through Conan's tissue and bone.

"I cut the arrow and dragged him into the minivan and took him up to the vet," said Liam O'Hara.

"He had a lung punctured, lost a lot of blood," Kevin said.

The family took Conan to a clinic for emergency surgery. At first the veterinarian who operated on Conan thought the dog had a good chance to recover because the arrow missed most of the dog's vital organs.

But Conan died at about 9:30 a.m. on Thursday the family said, due to massive internal bleeding.

The owner thought Conan might have gotten himself in trouble by wandering into someone else's yard, but he soon realized Conan had been attacked on his home turf.

Liam found evidence that indicates the person had shot several arrows, one of which was still lodged into the side of the house.

"And then I looked closely at the dog door and realized there were three holes in the dog door," Liam said.

Everything points to an intent and malice, Liam said, but the motive is still unclear.

"The only thing I can think of is somebody was upset because they were barking at him," he said.

"It's just unacceptable to think somebody's out there doing that and might come back," added Kevin.

Anyone with information on the case is urged to contact the family at (206) 288-3042 or police detectives at (206) 615-0512. Animal Control can be reached at (206) 386-PETS.