Scotland's papers: 'MI5 was warned'
Armed troops are to guard nuclear power plants in Scotland and other sensitive sites across the UK, as the police said they were now investigating a "network" linked to the Manchester bomber, writes The Herald.
The Daily Record says Britain was on lockdown with troops patrolling the streets amid fears those behind the Manchester bombing are ready to unleash "fresh carnage at any moment".
The National says that while Theresa May sent the army on to the streets on Wednesday, Scotland's top cop refused to allow "squaddies" into city centres, insisting his force had "sufficient resources" to deal with the current terror threat level.
The Courier also reports that military personnel will not patrol Scotland's streets under the anti-terror plans enacted in the wake of the Manchester attack.
The Manchester suicide bomber's "network" is the focus of the huge counter-terrorism investigation into the atrocity, as members of his family were detained in Libya, reports The Scotsman.
A relative of the Manchester bomber warned the British authorities that he was "dangerous", according to claims in The Times. The paper says that Salman Abedi's support for terrorism was reported this year to the security services, and friends had called Britain's anti-terrorist hotline five years ago with concerns about his views.
Likewise, The Telegraph says Abedi was "repeatedly flagged" to the authorities over his extremist views, but was not stopped by officers. The paper says that counter terrorism agencies are facing questions over the issue.
The Scottish Sun features an image of a young girl in the arms of a police officer in the hours after the Manchester bombing and says the child lost her mother, Michelle Kiss, to the blast.
Under the headline, the Jihadi Family, the Scottish Daily Mail writes that two close members of the Manchester bomber's family are in custody in Libya after the hunt for a network behind the bombing escalates.
Britain's terror alert level was raised to critical during a massive counter-terror operation - meaning another attack is "imminent" - as six suspects were held in raids, says the Scottish Daily Express.
The Daily Star of Scotland leads with claims by Salman Abedi's father that his son is innocent of the bombing and was looking forward to becoming an uncle.
The Press and Journal reports on the vigil held for two girls from Barra who were caught up in the blast and quotes Dr Rev Lindsay Shluter saying it was a time for the community to come together.