A masked gunman shouting “Free Palestine” opened fire at a wedding reception in Nashua, New Hampshire, killing 59-year-old guest Robert Steven DeCesare just before the bride and groom’s first dance.

Police identified the shooter as 23-year-old Hunter Nadeau, who was arrested and charged with murder.

At least six others were hospitalized with injuries while fleeing, and initial reports of multiple shooters led to a large manhunt before authorities confirmed Nadeau acted alone.

Witnesses described chaos as guests dove for cover during the gunfire, the New York Post has reported.

Nadeau faces additional charges for the injured victims and is due in court on Monday.