BERLIN — German police have conducted a large-scale anti-terror drill at Cologne-Bonn airport, in the west of the country, amid ongoing concerns about the threat posed by Islamic extremists.

Some 1,000 officers took part in the exercise early Wednesday, which took into account insight from attacks in neighboring Belgium and France to be as realistic as possible.

The scenario involved a group of extremists with military training seeking to cause as many civilian casualties as possible.

German news agency dpa reported that that drill involved a mix of regular police officers and special operations units, as well as 300 actors representing members of the public.

Two years ago, a Tunisian man drove a hijacked truck into a busy Berlin Christmas market, an attack that claimed 12 lives.