A bushfire in the Blue Mountains National Park was sparked by a father and son who allegedly torched clandestine meth labs the day police were supposed to raid the multimillion-dollar operation.

NSW Drug Squad police charged Peter Martin, 55 and Jim Martin, 27, both of West Hoxton, on Sunday night after two laboratories deep in bushland 60 kilometres west of Camden were set on fire last Wednesday.

Fire quickly spread through the Blue Mountains National Park and was only extinguished on Sunday night after six aircraft and dozens of Rural Fire Services volunteers fought the blaze.

More than 50 hectares of bushland was destroyed while numerous properties and lives were at risk as record temperatures caused havoc for emergency services last week.