It was spotted on the A90 towards the Forth Road Bridge.
Armed Police Won't Do 'Routine Patrols'
Armed police will now only be deployed to life-threatening incidents or those involving firearms, following a review by the chief constable.
Sir Stephen House has decided that his 275 officers attached to armed response vehicles will retain their standing authority to carry guns but that they will be not be dispatched to routine incidents.
There were 2,805 firearms deployments across Scotland between April 1 and August 31 - the equivalent of more than 150 a day, Police Scotland said.
Some politicians and members of the public have raised concerns about armed officers attending incidents such as road accidents and petty crimes.
Sir Stephen has approved the recommendation of the Armed Policing Monitoring Group (APMG) that the national standing firearms authority be continued, but officers attached to armed response vehicles will now only be deployed to firearms incidents or where there is a threat to life.
Armed officers will still have discretion to intervene if they see a crime in progress in the course of their duties.
The Chief Constable's decision "took into consideration the concerns voiced by politicians and some members of the public'', Police Scotland said.
A working group has been established to decide whether the carriage of firearms and tasers should be "overt or covert'' - whether they will carried on display or concealed.
The group will submit a preliminary report to the next meeting of the APMG in January 2015.
Deputy Chief Constable Iain Livingstone said: "Protecting the public and ensuring that all communities have the same access to specialist policing support, no matter where or when they need it, is at the heart of this decision.
"We have balanced our overriding duty to keep people safe with consideration of the views expressed about the perception of armed officers supporting local policing activities.
"Having a small number of armed police officers available means we can retain our operational flexibility and ensure that more than 98% of our officers remain unarmed but we remain best-placed to support the public when the need arises. The public would expect nothing less.
"The threat of firearms and other serious criminality does not discriminate between the city or the town and the rural community, or indeed the Highlands and the Borders.
"Just last week our armed officers were deployed to a number of high-profile incidents that occurred in 10 out of our 14 local policing divisions, including those believed to be the most remote and the safest across Scotland.
"The Chief Constable recognised the concerns expressed about the deployment of armed officers.
"As an organisation we acknowledge the local feeling from politicians and some members of the public, as evidenced by the feedback from several local authorities.
"We have listened to those concerns and this has resulted in the Chief Constable's announcement today.
"We welcome the ongoing reviews by HMICS and the Scottish Police Authority (SPA), and we will consider carefully the findings of these reviews in the context of taking forward our recommendations.
"The decision to continue with a small number of armed officers dedicated to specialist firearms duties is entirely proportionate and necessary, and ensures we discharge our duty to keep people safe.''
Deputy Chief Constable Simon Chesterman, lead on armed policing at the Association of Chief Police Officers (Acpo), said: "Whilst the establishment of a standing firearms authority is an operational matter for the chief constable of Police Scotland, as the armed policing lead for the Acpo I am invited to all meetings of the Police Scotland APMG and attended the meeting on September 16.
"I was able to confirm to the group that similar standing authorities, based upon informed strategic threat and risk assessments, are in place within almost every police force in England and Wales.
"The information provided to this meeting was appropriate and relevant to allow an informed decision to be made and, based on my understanding of the prevailing threat and risk, I consider the arrangements instigated within Police Scotland to be both proportionate and necessary.''
An SPA spokeswoman said: "We note the update from Police Scotland on their latest quarterly review of the standing firearms authority and welcome the commitment to considering the findings from the complementary reviews now under way by both HMICS and the SPA.
"The SPA's recently-launched public call for evidence is a tremendous opportunity for the nature and level of any concerns on the impact of the standing firearms authority to be captured.
"The visibility of firearms, how armed officers are deployed on routine duties and also how policing considers the wider community impact of policies are all key issues on which we seek feedback.
"This assessment of public impact, together with the assurance work of HMICS and emerging thinking from Police Scotland, will all inform the outcome of the SPA's scrutiny inquiry which will be delivered before the end of the year.''
APMG is a restricted top-level gathering of senior officers from around the UK.
It is not public facing and is not attended by civilian oversight body the Scottish Police Authority, although the SPA said it has been kept informed of its deliberations.
The group met on September 16 and reviewed updated intelligence on legally held firearms, classified information on serious organised crime groups and the number of firearms deployments between April and August.
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