A warning has been issued over the "appalling" hunting of wild deer at a nature reserve in Hull after illegal traps and snares were found there.
Humberside Police said the animals were being targeted at the Noddle Hill Nature Reserve in Bransholme "over recent months".
Officers said they were increasing patrols to "prevent further incidents" and make the site safe.
The animal is protected in the UK under the Deer Act, introduced in 1963.
Residents spotted "people who looked like they were hunting" and found evidence of traps and snares at the site, which have been reported to the police and local authority, the force said.
Councillor Mike Thompson said: "I'm appalled at the behaviour of a small minority who think it is acceptable to target wildlife on the reserve."
He said the council and police were working together to do "everything in our power to prevent the terrible actions of these individuals and protect the wonderful wildlife".
Sgt Steve Hepworth, of Humberside Police, said it was "very sad".
"I would say to anyone who has been setting traps or trying to kill the wildlife in the reserve that we will do everything we can to stop you, killing deer is illegal and we will do what we can to bring you to justice.
"We have plans in place to increase night-time police patrols in the park with volunteer Special Constables dedicating their time at weekends to keep a watchful eye on the area," he said.
The reserve has also attracted anti-social behaviour in the past 24 months with police receiving "frequent calls about fires being set" and "people causing injury and sadly death to animals", a police spokeswoman said.
She said there was "a noticeable decrease in the number of deer over the past few years" at the site, but there "may be a number of reasons for this decline" with the animal moving "freely in and out of the reserve".