A series of bizarre cat deaths in the Bristol area has seen the death toll rise to more than 20 this year.

In the latest spate of incidents, nine cats with suspected anti-freeze poisoning have been found dead or have had to be put down in the Brislington area.

The deaths have led to a warning by vets at Bristol-based Highcroft Veterinary Group.

All cases except one have been cats in the Brislington area, mostly around Wick Road.

All have either died or been put to sleep.

The vets have no idea how these cats came to be poisoned by antifreeze but there are a number of possibilities.

A spokesman said: "One is that they had been drinking water from a pond that had anti-freeze added to it to avoid it freezing over in the cold weather.

"The practice is urging all cat owners to be vigilant when handling anti-freeze products and to look out for spillages or leaks.

"It is very palatable to cats as it tastes sweet but it is extremely poisonous."

Anti-freeze poisoning causes acute kidney failure and by the time the clinical signs are apparent it is almost always too late to treat successfully – treatment would need to be within minutes of ingestion.

Any cat owners worried that their cat is behaving strangely – vomiting, not eating, lethargic, wobbly or having seizures – should contact their veterinary surgeon, or call Highcroft on 01275 832410.

Other incidents include a kitten in Withywood which had to have it's leg amputated after it was believed to have been shot, shortly before two other cats in the area disappeared.

And in February, 13 cats were found dead or dying in Little Stoke, again from possible poisoning.

Eight-month-old Doon is now walking on three legs after she was apparently shot by an air gun pullet.

Her owner Hannah Walker, 41 of Sherrin Way, said she came home on Valentine's Day crying and clutching her paw.

PDSA vets X-rayed the cat and discovered an air-gun pellet lodged in her elbow joint.

Due to the position of the pellet and resulting bone damage, the staff had to amputate the leg.

Ms Walker said: "As she's a kitten she's adapted really well but she looked hideous when she came home, like something out of a horror movie.

"They spayed her as well so she had patches of hair missing and a scar down her front, and she was left with a stub at the top of her front leg.

"It's a really cruel thing to do. I heard there was another one in Knowle so I thought someone had taken up shooting cats."

Linda Stewart, senior veterinary surgeon at Bristol PDSA PetAid hospital, said: "We see several cases of pets being injured or killed by air guns every year.

"Every case is very distressing, though we haven't noticed a significant rise in numbers over the years.

"We advise owners to report such incidents to the RSPCA for investigation."

Ms Walker became particularly concerned after reading in the Bristol Post about two cats going missing in the Withywood area.

Marnie Lord and Jennifer Davis, both 28, lost their cats in the last month.

They contacted pet detectives Animal Search UK, an organisation dedicated to organising volunteers to help track down pets that have gone astray.

The firm believes the two disappearances may be connected.