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 pre-trial detention.

The request came after hours of questioning of the bar’s co-owners. Some 40 people died in the fire that broke out during a New Year’s celebration.

The request came after hours of questioning of the bar’s co-owners. Some 40 people died in the fire that broke out during a New Year’s celebration.

The request came after hours of questioning of the bar’s co-owners. Some 40 people died in the fire that broke out during a New Year’s celebration.

The request came after hours of questioning of the bar’s co-owners. Some 40 people died in the fire that broke out during a New Year’s celebration.

As the nation mourns the 40 victims of the Swiss bar fire, authorities move forward with criminal investigation.