Britain’s MI5 intelligence service has raised the terror alert level for Northern Ireland to “severe”, meaning an attack is highly likely, the British government said on Tuesday, Reuters quoted.

Chris Heaton-Harris, Britain’s minister for Northern Ireland, said in a press release that the alert level had been raised from “significant” following the recent attack on several police officers.

The officer was seriously injured off duty after being stabbed last month, an incident condemned by the UK and Irish governments.

“The public should remain vigilant, not worry and continue to report any concerns they have to the Police Service of Northern Ireland,” says Heaton-Harris.

The change comes about a year after British intelligence lowered its alert level for Northern Ireland to “significant” for the first time in more than a decade.

It also comes ahead of the 25th anniversary of the signing of the Good Friday Agreement, which largely ended three decades of violence that had rocked Northern Ireland since the late 1960s.

Earlier in March, US President Joe Biden announced that he had accepted the invitation of British Prime Minister Rishi Sunak to visit Northern Ireland.

Ex-President Bill Clinton and his wife Hillary Clinton, former US Secretary of State, are also expected to attend the anniversary events.