Police Scotland, the Fire Service and the Explosive Ordnance Disposal Unit were called to the Sighthill delivery office on Cultins Road at around 10.30am on Saturday.
The Scottish Sun are reporting that the package was ‘smouldering’ and had the First Minister’s name written on the front.
Police Scotland said the building was partially evacuated “as a precaution” and that the incident was not thought to be a threat to the wider community.
Recalling the drama one source told The Sun: “It was terrifying.
“Imagine if a letter dropped through your letterbox and it started to emit smoke and smell. You would be rightly terrified and get the hell out of there.
“At the end of the day, everyone is alright on this occasion and that’s the main thing. Staff are trained to deal with this sort of thing and what to do if there’s a suspicious package.
Officers remained at the scene until around 5pm.
One staff member at the delivery office who did not want to be named said employees were “in shock” after discovering the package.
She added that in two decades working with Royal Mail this was the first time she had experienced an evacuation like this.
A Police Scotland spokesperson said: “We were called around 10.25am on Saturday, 14 November, to a report of a suspicious package at a sorting office in Cultins Road, Edinburgh.
“Officers attended along with colleagues from the Scottish Fire & Rescue Service, supported by the EOD (Explosive Ordnance Disposal).
“The building was partially evacuated as a precaution and later re-opened once EOD removed the package.
“Enquiries into this are ongoing.”
And a Royal Mail spokesperson said: “Royal Mail can confirm that a suspect package was found at Edinburgh Mail Centre.
“The safety of our people is of the utmost priority and in line with our policy and procedures, emergency services were called.”
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