Substantial continues to indicate a high level of threat," Home Secretary Priti Patel said in the statement LONDON: Security officials downgraded Britain’s terrorism threat level on Monday from “severe” to “substantial,” with officials saying the country now sees an attack as “likely” rather than “highly likely.” The assessment was made by the Joint Terrorism Analysis Center, an independent expert body that evaluates intelligence, terrorist capability and intentions. It was announced in a written ministerial statement to Parliament. “Despite the change in the threat level, terrorism remains one of the most direct and immediate risks to our national security,” Home Secretary Priti Patel said in the statement. “Substantial continues to indicate a high level of threat; and an attack might well occur without further warning.” The change in the level is a positive development but hasn’t eliminated the threat of terrorism, said the head of counterterrorism policing, Neil Basu. He said about 800 investigations are still underway nationally and 24 attack plots have been thwarted since March 2017, when 52-year-old Khalid Masood fatally struck four people with a car at Westminster Bridge then fatally stabbed a police officer before security forces shot and killed him in a courtyard outside Parliament. “It is vital that we all maintain a high level of vigilance and continue to invest in strong protective security measures to deter future attacks,” Basu said. He added that with the pending holidays and December election, “our towns and cities will be extremely busy.” “So we appeal to everyone to please remain vigilant.” The UK’s terror threat was last listed as “substantial” in August 2014; since then it has held steady at “severe,” briefly rising to “critical” in May and September 2017.