Flights in and out of Rome's disaster-hit Fiumicino airport were seriously disrupted for a second day today after a fire in a nearby pine grove threw dense smoke across the runway.
The blaze yesterday forced the suspension of all flights for two hours, with long delays stretching into the night even after the fire was brought under control.
Today most flights out of the Italian capital's busiest hub were at least an hour late, with a 20-minute power cut in the terminal adding further to the chaos and infuriating delayed passengers.
Italian television showed images of exasperated travellers venting their anger.
The airport was last forced to close in May after a blaze devastated part of a terminal which has yet to fully reopen.
Interior Minister Angelino Alfano confirmed that an investigation had been opened after authorities found that Wednesday's fire started in multiple places, leading them to believe it was started deliberately.
Fiumicino mayor Esterino Montino said the blaze had spread on a front about one kilometre (half a mile) wide.
"The fire seems to have started in two or three different places," he added.
May's blaze was triggered by an electrical fault in a bar which sparked scenes of total chaos, with thousands of people hit by flight cancellations and airport staff forced to wear protective masks.
Terminal three, which handles international flights, was seriously damaged and the airport was forced to reduce capacity by 40 percent.
Italy's civil aviation authority ENAC has called an August 6 meeting with airport chiefs and Alitalia, which runs half of all flights from Fiumicino, to "verify their capacity to react" to crises after Wednesday's chaos.
