US school shooting: many dead
Many others were injured when an assailant opened fire at Marjory Stoneman Douglas High School in Parkland, Florida.
Police responded to first reports around 2.30pm local time on Wednesday (6.30am Thursday AEDT).
A fire alarm reportedly went off just minutes before the shooting started. Students were evacuating the school when the gunfire began.
CBS reports that students initially thought the shooting was a drill, after they had one earlier in the day.