Firefighters were called to a Wigan estate after a shipping container full of propane cylinders caught fire and exploded in a potentially "malicious" act.
Wigan and Leigh firefighters were called to reports of a container fire at around 3pm and spent two hours tackling the blaze on a vacant council estate near Christopher Street in Ince.
A 50m cordon was put in place around the fire and police visited nearby houses to warn people to stay indoors in case of an explosion.
Firefighters used a ground monitor which they placed around 25m from the burning container, to dispense "copious amounts" of water while the teams could remain at a safer distance until it was brought under control.
Watch manager Carl Gleaves said: "There were butane and propane cylinders inside which posed quite a significant explosion risk.
"Luckily the newer models have blow off valves which keep the explosion more controlled resulted in a huge fire ball and a loud noise.
"The older cylinders can explode causing projectiles and we weren't able to establish what type they were on arrival so created a cordon for safety."
Although the fire is believed to be an act of arson, watch manager Gleaves is warning people to lock away any flammable materials and keep them well shaded during the current heatwave as they can spontaneously set alight.
A police investigation has been launched into the cause of the fire.