Nicola Sturgeon said the authorities cannot be sure there are no other Scots affected.
Clubs' Tributes To Young Footballer
Tributes have been paid to a young footballer who has died at the age of 20.
Jack Syme, from Abernethy, was a regular member of Forfar Athletic's under-19 team last season.
He also played for St Andrews United on a temporary transfer.
He was last seen on Sunday in the Kinnoull Hill area of Perth.
A body was found at the foot of the hill yesterday and Mr Syme's family have been informed.
Police said there are no suspicious circumstances surrounding the death.
In a statement yesterday, Forfar Athletic said: "All involved with Forfar Athletic Football Club are extremely saddened and distressed with the news today of the untimely death of our 20-year-old defender Jack Syme.
"Jack, who hailed from Abernethy, was a regular member of our under-19 team last season and had, in fact, been farmed out on a temporary transfer during the first half of this campaign to St Andrews United.
"At this sad and difficult time, the thoughts and sympathies of the directors, management, coaching staff and players at Station Park are with Jack's mother, family and friends.''
A Development League match between Forfar Athletic and Raith Rovers FC has been postponed as a mark of respect.
St Andrews United also paid tribute to the young player.
The club said: "The thoughts of St Andrews United FC are with Jack's family and friends at this difficult time.
"Rest In peace, Jack.''
Family members say Laura Macintyre and Eilidh MacLeod haven't been heard from since the explosion.
The families of two girls from the Western Isles missing after attending the concert in Manchester targeted in a terror attack have issued appeals on social media.
Crews were called to the former Royal Victoria Hospital site this afternoon.
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