Terrorist threat level from Northern Ireland remains moderate

And according to the MI5-based Joint Terrorism Analysis Centre the threat to Northern Ireland and its citizens from Northern Ireland-related terrorism is severe.

MI5 is responsible for setting the threat levels from Irish and other domestic terrorism in both Northern Ireland and in Great Britain. The current threat level has been in place and unchanged since March 2018.

Threat level is gauged by a number of factors including available intelligence, terrorist capability and terrorist intentions.

The Metropolitan Police said on Tuesday that the public should remain vigilant.

"Extensive advice has already been issued to relevant businesses and sectors to be vigilant for and report suspicious packages to police," a statement said.

"This advice was previously sent to armed forces personnel and is being reiterated again in light of this claim.

"We continue to urge the public to remain vigilant and report anything suspicious to police.

"Suspicious activity can be reported by calling the confidential phone line 0800 789 321 or filling in a secure form at www.gov.uk/act. In an emergency always dial 999."

According to the Home Office, the threat to the UK, including England, Wales, Scotland and Northern Ireland, from international terrorism remains severe.