COPENHAGEN, Denmark (AP) — A 23-year-old man appeared in a Danish court on Friday, a day after being arrested on suspicion of plotting an extremist attack. He was ordered jailed until May 28 as investigations continue.

The man, who cannot be named under a court order, is suspected of attempting to acquire one or more firearms for what police have called “a terror attack with a militant Islamic motive."

He denied the accusations when he appeared at a behind-closed-doors court hearing in the capital, Copenhagen, along with his defense lawyer, Steffen Thorborg.

It was not known when or where the alleged attack was to have been staged.

The suspect, who was arrested Thursday in the Danish capital, likely acted alone, according to police.

Danish authorities have reported foiling several extremist attacks in recent years, including ones linked to the 2005 publication in a newspaper of 12 cartoons by various artists depicting the Prophet Muhammad.