Firefighter dead, one injured in SA blaze

A firefighter is dead and another seriously injured after a tree collapsed on a fire truck battling an out-of-control bushfire in South Australia's southeast.

The tragic incident occurred at the firefront at Coles, near Lucindale, where the blaze is running uncontrolled through bluegum plantations, scrub and grassland, a Country Fire Service spokeswoman confirmed.

The injured firefighter has been rushed to hospital.

"Family and other personnel have been informed and are being offered support at this time," the CFS said in a statement.

"The safety and wellbeing of our people is our highest priority and our thoughts are with our CFS family at this time."

Premier Steven Marshall on Friday night lauded the firefighters as heroes, and expressed his great sadness for the family of the person who died.

"CFS members are always ready to respond when their community needs help to save life and property," he said in a statement posted to social media.

"My thoughts are with their family, friends, the local community and of course all members of our selfless emergency services during this difficult time."

More than 150 firefighters are monitoring the blaze, which has been burning for several days but is not considered an immediate threat to lives or homes.

In an update on Friday night, the CFS said the blaze, which has already destroyed about 2000 hectares, would keep crews busy well into the night.

"Mourning the loss of one of their own while another remains in a serious condition in hospital after an incident on the fireground involving a falling tree, CFS crews will actively continue working along the fires' perimeter," the update said.

SA CFS crews on the ground are being supported by crews from Victoria along with forest industry units and local farmers.

Water bombing aircraft have also been deployed.

Victorian Country Fire Association Chief Officer Jason Heffernan on Friday afternoon said his crews were also shattered by the incident.

"CFA stands with our CFS colleagues on the fireground, and in grief," he said in a statement.

"Firefighting is an inherently dangerous activity and I am grateful and proud of the commitment and sacrifices that Australian firefighters make every day."

The CFS said locals should stay vigilant and monitor conditions throughout the next few days as it was expected that the conditions will continuously change.