Following the recent suicide attacks in Brussels, some officials said that the city was unprepared for acts of terrorism.
ISIS has claimed responsibility for the bombings that struck the Belgian capital’s airport and metro. At least 31 people have been killed and dozens were injured. Since the attack, the city has been on lockdown and has increased security.
European officials said they had been bracing for a major assault and also warned that ISIS was getting ready to attack.
“What we feared has happened,” said Belgian Prime Minister Charles Michel.
“In this time of tragedy, this black moment for our country, I appeal to everyone to remain calm but also to show solidarity,” he added.
The attack comes just days after a suspect of the Paris attacks, Salah Abdeslam, was arrested in Belgium.
After the arrest Foreign Prime Minister Didier Reynders said Abdeslam was “ready to restart something from Brussels,” noting that “a lot of heavy weapons” were found during his apprehension.
The magnitude of the Brussels attacks suggests that it may have been planned for some time.
“The speed at which this attack occurred suggests that the network had likely been preparing for this attack in some manner for many weeks or months prior to Abdelslam’s arrest,” said Clint Watts, a former FBI and U.S. Army counter-terrorism official, on the Foreign Policy Research Institute’s website.
He also said that Belgium “appears to have both a capacity and competency problem with regards to counterterrorism,” since it failed to detect the recent attack and for taking too long to arrest Abdeslam who was on the run for months.
“That they could sit for four months, not only in Belgium but in Brussels and especially in Molenbeek, and plot these kinds of attacks just four days after the arrest of such a high-level network facilitator — this is shocking to me because they should have been on the highest level of alert,” said Watts to NBC News.
“It is hard to conceive that this would happen on such a large scale when it was so obvious that these guys were operating there,” he said about ISIS.
“After [Abdeslam’s] arrest, you would have to assume everyone in the network was preparing to launch whatever they had,” Watts added.
Meanwhile, Belgian officials admitted that they were surprised by the scale of the attacks in Brussels.
Interior Minister Jan Jambon stated, “it was always possible that more attacks could happen but we never could have imagined something of this scale.”
The Associated Press contributed to this report.