Police and volunteers are taking part in a major mountain rescue exercise to hone their skills for winter.
More than 70 people are participating in the exercise, which involves Police Scotland officers from Forth Valley Division along with volunteers from Killin, Lomond and Ochils mountain rescue teams (MRTs).
The rescuers are responding to a scenario involving a group of four missing walkers, while a second scenario with a further two casualties will be added later in the day to add to the complexity of the incident.
Last year alone, Scottish #MountainRescue teams volunteered 22,697 hours of their time. We are incredibly proud to support the life-saving work they do. Read more here: https://t.co/RKA53hL5VS ... @ScottishMR ?
-- St John Scotland (@StJohnScot) October 19, 2017
Police said people may notice increased emergency services activity in certain areas around Crianlarich on Sunday as the exercise takes place, but said they should not be alarmed by this.
The exercise will allow police and volunteers to plan and prepare for search and rescue incidents in the mountains of the Forth Valley.
It will not affect day-to-day policing or emergency service responses, which will continue as normal throughout the exercise, police said.
Pc William Diamond, mountain rescue co-ordinator for the Forth Valley area, said: "Winter is one of the most dangerous times of year for those taking part in mountain activities.
"As the temperature and number of daylight hours decrease, the stakes for both police, volunteers and those being rescued become much higher.
With snow slowly building on the higher tops, it's just the right time to refresh you avalanche awareness skills!... https://t.co/OR5pXKRfC5
-- Lomond MRT (@LomondMRT) November 21, 2017
"We make use of a range of specialist resources to assist in locating those who are lost and injured in the mountains, including helicopters and search dogs; however, it is the local mountain rescue teams who undertake the vast majorities of searches and rescues.
"The three mountain rescue teams within the Forth Valley area are Killin, Lomond and Ochils MRTs.
"Each team comprises of volunteers who will readily assist those who need help in our mountains. There are also a number of local police officers who are also volunteers within the teams.
"There will be noticeable activity in the Crianlarich area on Sunday and the public can be assured that this all forms part of these live-play scenarios and there is no risk to the public."
He advised people heading into the hills this winter to plan their visit, dress for the weather and know their limits, and also urged people to leave some basic information including their intended route and return time with someone.
Chief Superintendent Thom McLoughlin, divisional commander for Forth Valley, said: "Mountain rescues can be difficult and risky for those involved.
"Therefore it is essential that both police personnel and volunteers have a strong understanding of the risks involved and the difficult and potentially treacherous conditions they could face.
"I would like to thank both the officers and volunteers who are taking part in today's exercise. It is the culmination of months of planning and we hope the scenarios will be realistic, challenging and complex in nature in order to robustly test those taking part."
Bill Rose, of Killin MRT, said: "The three teams train regularly in order to practise their skills, and by working together on an exercise such as this, it allows the sharing of ideas as well as practising how the teams can work together, which is often required on larger searches or avalanches."