Jockey Tom Scudamore is among those expressing concerns about drones over racecourses.
Officials at Leicester have voiced their frustration with the subject of drones on racecourses again in focus.
It is believed images from drones are being used to give in-running punters an unfair advantage on betting exchanges as the streamed pictures may be a few seconds ahead of TV channels.
There was a reported sighting at Haydock on Saturday and at Leicester on Tuesday.
“I’ve seen it twice today,” racecourse chairman Nick Lees said.
“They are flying it from an old factory on the other side of the racecourse on the roof. They launch it from there.
“He’s done it before, when we’ve been in touch with the Civil Aviation Authority and the police.
“In the past he once tried to use a Cherry Picker, but he was stopped. There are CAA rules, but this chap responsible says he isn’t breaking any rules.”
Leading jockey Tom Scudamore, who rode a winner on the card, did not see the drone himself – but did suggest the devices could potentially impact on the safety of people arriving at tracks by air.
“There is a lot of aviation going on around racecourses, with people arriving and leaving by helicopter or aeroplane, and that is obviously a concern if there are drones flying around,” he said.
“I know there there is some use of them (drones) on television, but then it is correctly operated and they know about any helicopters or aeroplanes that are arriving at the track.
“I didn’t notice it today and I was also riding at Haydock last Saturday, where I believe there was a drone.
“There were some concerns about a drone at Newmarket a couple of years ago and a few younger horses were getting spooked, but in that instance the drone was flying low and obviously closer to the horses.”
The Racecourse Association works on behalf of all 59 British tracks and has already begun to address the subject, but says the issue is not easy to resolve.
“The RCA takes a proactive lead providing guidance to racecourses around drone usage,” Caroline Davies, RCA racecourse services director, said in a statement last week.
“This involves best practice from the Civil Aviation Authority and other relevant authorities as well as taking into account how other venues have handled similar situations.
“Given the recent emphasis on drone safety, racecourses are revisiting their risk assessments. The safety and enjoyment of all racegoers is of the utmost priority.
“Whilst frustrating, if the operator is not breaking the law there is limited further action that can be taken at this time.”