Fires in Australia pop up in places already burned

Fires that span across the Northern Territory and Western Australia appear to have broken out in areas that have already been burned in previous fires. Areas that sport "burn scars", those areas that are a darker, almost red-brown color, are surrounded by fires that are anywhere from a few hours old to 7 days old. The areas that are seven days old can be attributed to fires that spread but areas that are just a few hours old may be fires that have presumably been put out only to have them break