Switzerland held a national day of mourning on Friday for the 40 people who died in an Alpine bar fire during a New Year’s Eve celebration, as prosecutors requested one of the managers to be placed in pretrial detention.

Valais region’s chief prosecutor Beatrice Pilloud said in a statement the detention of the man was needed to avoid a “risk of flight.” The man’s wife and co-manager will remain free under judicial supervision, the statement said.

A Swiss business register lists French couple Jacques and Jessica Moretti as the owners of Le Constellation bar, in the Alpine resort of Crans-Montana, where a fire broke out less than two hours after midnight on Jan. 1; 116 others were injured, many of them seriously.

Local media reported that Moretti was being held in custody pending the court’s decision after the couple were questioned by prosecutors in Sion on Friday morning.

Swiss authorities have opened a criminal investigation into the owners, who are suspected of involuntary homicide, involuntary bodily harm and involuntarily causing a fire.

— The Associated Press