A group of teens hurled rocks at a guardian donkey after trying unsuccessfully to ride it.
The donkey has been tasked with watching over goats inside parkland in Pittsburgh, in the US state of Pennsylvania.
The goats are clearing out a destabilised hillside and overgrown vegetation at South Side Park, according to KDKA.
Allegheny GoatScape, who brought the goats in, placed them deep inside the parkland to ensure their protection, but last week six teens managed to attack the donkey.
Sarah Baxendell from Hilltop Alliance, a community organisation looking after the hill areas of Pittsburgh, said the teens were trying to ride the donkey.
“And then once she [the donkey] yelled at them, they started to hurl rocks at the donkey,” Ms Baxendell said.
The donkey is OK, but earlier this month someone also tore down part of the fence, which was keeping the animals enclosed on the site.
The person also stole solar batteries that were powering the fence.
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The animals have remained in the site but neighbours are angry about the attacks against them.
“They’re really doing something beneficial to our neighbourhood, so it’s really terrible that someone is doing that to our neighbourhood,” Megan Devitt said.
The goats and the donkey will be taken away in a couple of weeks.
The neighbourhood will then reseed and plant the hillside to make it a usable green space.
Pittsburgh Police have also increased patrols in the park to stop intruders.