FIFTEEN fires are burning out of control in NSW, with 126 fire fronts still burning two days after the state sweltered through a heatwave.

The pressure is now on to contain the blazes by tomorrow when the heat is forecast to return.

Total fire bans are in place in the state's north, including Gunnedah, Gwydir, Inverell, Liverpool Plains and Tamworth.

Bans are also in place in the North Western region encapsulating Moree Plains, Narrabri, Walgett and Warrumbungle.

Meanwhile, police continue to investigate a fire near Lithgow, in the Blue Mountains west of Sydney, which destroyed about 40-thousand hectares yesterday and is believed to have been deliberately lit.

NSW Premier, Barry O'Farrell, who visited bushfire zones around Wagga Wagga yesterday, has backed a plan to force arsonists to help put down animals injured in fires.
Mr O'Farrell and Prime Minister Julia Gillard, have announced natural disaster assistance in 37 local government areas in NSW.