Police couldn't have prevented the death of a man who drowned in a quarry, a watchdog has found.

Mark O'Brien's friends called emergency services after they saw him jumping into the water and failing to resurface at Craigiehill Quarry in East Ayrshire at about 8.30pm on Monday, May 28.

The 28-year-old's body was recovered later that evening, with the cause of death given as drowning.

Mr O'Brien's death came hours after the quarry supervisor had contacted police to report evidence of people using the quarry over the weekend.

In his phone call at 2.53pm, he asked police to give the area attention while on patrol, but did not request them to go to the scene at that time as was no indication anyone was at the quarry at that moment.

Due to other local demands on policing, no resources were available at that time and as there had not been any other calls about the quarry by around 8pm, the incident was closed.

Police watchdog, the Police Investigations and Review Commissioner (Pirc), said there was "no evidence that if the police had attended the quarry on the afternoon of May 28, 2018 that the subsequent death of the man later that evening could have been prevented".

Between 2015 and 2018, there were 11 reports made to Police Scotland over concerns about people using the quarry, near Kilmarnock.

The Crown Office asked Pirc to investigate the circumstances leading up to the incident on May 28, in particular the background of the earlier reports to Police Scotland and the fact that no officers were available to respond to the concerns raised by the quarry supervisor.

The watchdog found that Hillhouse Quarry Group Ltd, the private company which owned the quarry, had sole responsibility for its safety and security, and had put up boundary fencing to try and keep people out, as well as danger signs warning people not to enter the water.

Investigators found the police response to the report made at 2.53pm on May 28 was "appropriate and proportionate to the circumstances reported".

Pirc also said there is no evidence that if the police had attended the quarry on that afternoon that the subsequent death of the man later that evening could have been prevented.

The watchdog also found that the police response to all previous reports made to Police Scotland had been "appropriate and proportionate to the circumstances reported".

Following the incident in May, Hillhouse Quarry Group said its thoughts were with the man's family and warned others to stay away.

In a statement at the time, the firm said: "The company would like to express its deepest sympathies to the victim's family and friends.

"The site is regularly inspected to ensure boundary fences and warning signs are maintained and life belts are available.

"The company asks that, for their own safety, members of the public keep away from the site and do not take access."