Armed police are stopping and searching children, it has been claimed.

Police Scotland has 275 officers with a standing authority to carry firearms while responding to routine calls, First Minister Alex Salmond has confirmed.

Liberal Democrat leader Willie Rennie claimed this has resulted in armed police carrying guns at road traffic accidents, during crowd control and while stopping and searching children.

Mr Salmond accused Mr Rennie of "hyperbole" and expressing "unnecessary fears" at First Minister's Questions, pointing out that all but one of England's police forces have the same firearms policy as Police Scotland.

Mr Rennie said: "Police Scotland has admitted that more armed police officers are ready and armed at all times, even on normal duties.

"So, we now have more police carrying guns at road traffic accidents, more police carrying guns controlling crowds outside nightclubs and carrying guns while stopping and searching children.

"The relationship between the police and the public is at risk.

"It was supposed to be that carrying guns was an exception, now it is being normalised."

He called for the appointment of an independent reviewer to look at the use of guns by the police.

Mr Salmond said: "There's 275 officers that have standing authority to carry firearms at the present moment while on patrol.

"That is out of a total number of police officers in Scotland, thanks to this government, of over 17,000.

"I think that sense of perspective should be placed in the realm of Willie Rennie.

"The alternative to them not being available for other duties, and let us remember that on any one shift it will be a fraction of 275, would be to have a situation where officers had to drive past incidents that they happen to be first responders to because they were armed officers.

"That would clearly be impractical and undesirable.

"Every single police board in England bar one has exactly the same operational response as the (Police Scotland) chief constable.

"I would like to know, given that his party is in government at the present moment, has he expressed his concern on these fears or these difficulties to his colleagues in government at Westminster, or does he just reserve his hyperbole coming along to this parliament expressing unnecessary fears and putting things in a way that is not at all reasonable?"

Assistant Chief Constable Wayne Mawson said: "We have received no complaint about armed officers carrying out a stop and search.

"The use of stop and search, where it is targeted, intelligence led and used in the right place at the right time, is an effective and legal tactic that helps Police Scotland support local policing priorities.

"Stop and search is one of a number of policing tactics we use to keep people safe. Searches of children have resulted in the recovery of alcohol, drugs and knives which can and do cause harm and injury to children and adults."