A much-loved pony has been fatally shot by arrows in a paddock in Darwin, the latest in what has now become a string of animal cruelty attacks in the area.

Despite efforts by a vet to save the 20-year-old pony known as Pearly, she was put down several hours later.

The injured animal was found in a paddock by a teenager from the Fannie Bay Equestrian Club (FBEC) about 4:00pm on Wednesday.

Many young children learnt to ride on the 20-year-old pony. ( Supplied: Inge van Sprang )

"Who does that to a defenceless animal, what sort of sicko does that?" Melanie Brenton, president of the FBEC said.

"In 40 years of being a member of this club I've never seen anything like this ever happen before."

Suspicion over injury on second horse

The owner of another horse in the same paddock said she was concerned her horse had also been targeted at the same time.

"It's an injury, I've just discovered. It's very circular and neat, it's very swollen and sore," Colleen Davidge said.

"He's in the same paddock as Pearl, so I'm a little bit concerned that perhaps this was a shot that didn't go according to plan.

"I'm just grateful that he didn't get hurt while he was out thee with poor old pearl. Shocking," Ms Davidge said.

Shooting follows East Point wallaby deaths

Northern Territory Police are now investigating the incident in what is the latest in a string of animal cruelty attacks in East Point Reserve.

Several wallabies were mowed down and killed by a car in three incidents late last month, which authorities believe were deliberate attacks.

"Wallabies are defenceless animals as well, I really can't fathom why anyone would do either of those acts," Ms Brenton said.

"But it's got to stop, we've got to find ways to stop it."

Pearly was privately owned but ridden by many at the club, including children learning to ride.

"She taught us how to ride, that was really special," 10-year-old Lalwa May said.

Lalwa and nine-year-old Anouk Chapman went to Pearly's stables on Thursday to commemorate her death.

"I cantered my first time on her and cantered bare-back on her and learned to jump, so she's very special to me," Anouk said.

The club is now reconsidering the level of security at the site in the wake of the incident.