There’s a makeshift memorial of flower bouquets and American flags at the fire station in Prescott, Ariz., where an elite team of firefighters was based.

Nineteen of the 20 members of the “Hotshot” team were killed yesterday when a wind-blown wildfire suddenly swept toward them in Yarnell, a mountain town about 85 miles northwest of Phoenix. The one firefighter who survived had been moving the team’s truck.

One man who left 19 water bottles in the shape of a heart says the news of the firefighter deaths hit him “like a ton of bricks.”

Arizona’s governor has ordered flags flown at half-staff.

The bodies of the 19 firefighters were brought to Phoenix today in a caravan of white vans. The medical examiner’s office in Phoenix will conduct autopsies.

President Barack Obama is predicting that the tragedy will force government leaders to address broader questions about how they handle increasingly destructive wildfires.

The fire exploded in size to about 13 square miles by Monday morning. It destroyed about 50 homes and is threatening 250 others in and around Yarnell.

Four hundred firefighters are now battling the fire. Yavapai Community Health Services says 200 more firefighters have joined the fight.

An automated call warning people to evacuate was sent, and sheriff’s officers are going door-to-door to make sure people get out of their homes.