Irish terror threat 'substantial'
An attack on Great Britain by Irish-related terrorists is a "strong possibility", Home Secretary Theresa May has said as the country's threat level was raised to substantial.
The threat assessment was increased after the head of MI5 warned that dissident Irish republicans could attempt to mount a new wave of terrorist attacks on the British mainland.
But it is still lower than the overall threat to the UK from international terrorism, published by the Joint Terrorism Analysis Centre (Jtac), which remains at severe, meaning an attack is highly likely.
Mrs May said: "The director-general of the Security Service has informed me that he has raised the threat to Great Britain from Irish-related terrorism from moderate to substantial, meaning that an attack is a strong possibility.
"Judgments are based on a broad range of factors, including the intent and capabilities of terrorist groups."
The assessment of the risk posed by Irish-related terrorism was published for the first time "to encourage people to remain vigilant", she said.
Mrs May added: "We have been consistent in stating that the threat to the UK from terrorism is real and serious.
"The balance we aim to strike is keeping people alert but not alarmed.
"I would urge the public to report any suspicious activity to the police and security services in their continuing efforts to discover, track and disrupt terrorist activity."
The public should not expect any visible change in security measures as steps taken to deal with the international threat will also counter the threat from Irish dissident republican terrorism, the Home Office said.