Nearly 1,000 people have signed a petition calling for Belvoir Castle to drop plans to hold a lantern light festival because they say it will be dangerous for nearby residents and animals.
Campaigners fear animals could suffer burns when the lanterns fall to the ground and some could be injured by eating bamboo used in them.
They also say there is a risk of property and fields catching fire when the lanterns drift away from the castle during the The Lights Fest, which is scheduled for July 7.
Heather Wright, who started the online petition, said: “We already have more than 900 signatures and it has only been running for 10 days.
“I have got horses in the proximity of the castle and I am really worried about them and other animals in the area.
“There are that many fires which have been caused by these lanterns at this type of event and I can’t believe Belvoir Castle is still going ahead with it.”
The campaigners have written to the Duchess of Rutland, who lives at the castle, asking her to cancel the event.
Ms Wright added: “The organisers say they use biodegradable lanterns now but it still takes them a few months to degrade completely and animals still eat them and suffer internal damage as a result.”
Leicestershire Fire and Rescue Service has voiced concerns over fire safety issues and says it has given advice to the organisers of the event and to the landowner.
Alan Fawkner, the brigade’s area manager community risk, said: “Leicestershire Fire and Rescue Service would like to reiterate our stance that we do not support or endorse the use of sky lanterns, or any events promoting their use.
“We stand by the national statement by the National Fire Chiefs Council, which states ‘floating lanterns not only constitute a fire hazard but also pose a risk to livestock, agriculture, camping activities, thatched properties and hazardous material sites’.”
Farmer Peter Copley called on Melton Council to ban anyone from putting on sky lantern events in the borough.
Mr Copley, of Manor Farm, Upper Broughton, said: “The wire and plastic from these lanterns can be spread over a wide area, but if it was dumped in a country lane in one pile the council would probably prosecute if they caught the culprit.
“Melton Council should follow the lead of many others and put a total ban on sky lanterns.”
The National Farmers’ Union (NFU) has also highlighted the risks of putting on the event.
A spokesperson for the East Midlands branch said: “NFU and other organisations, including RSPCA, the British Horse Society, Leicestershire Fire and Rescue Service and local councils around the country have many concerns regarding sky lanterns, but a mass release amplifies the risks involved.
“We have expressed our concerns to Light Fest.”
The Countryside Alliance also has misgivings about the planned lantern light event at the castle.
It said in a statement: “Helium balloons and Chinese lanterns can cause a real spectacle in the sky but they are also a real danger to the countryside, livestock and wildlife.
“Drifting for miles, they are a menace for farmers and landowners who frequently report sheep, cattle and horses being injured or even dying from eating the wire metal frames of the lanterns or being spooked by them.
“The Countryside Alliance does not want to be a party pooper but we ask people to think twice before letting them off and to consider the impact of them after they have left their hands.”
A spokesperson for The Lights Fest said: “We work hand in hand with local officials to make sure all concerns are addressed concerning safety and the environment.
“The lantern style that we are bringing to the event at Belvoir Castle will travel up to 500 yards and will not leave the venue boundaries.”