Updated

Rome's longstanding garbage problems turned into an emergency Tuesday after a huge fire at a waste disposal plant blanketed the Eternal City in smoke and forced authorities to scramble to find alternative facilities to treat the capital's trash.

The Salaria plant has been the subject of protests for years by residents complaining of putrid smells and demanding its closure. Arson was suspected, since the blaze put the plant out of operation indefinitely.

It also sparked shorter-term health concerns given the huge cloud of smoke that covered the city. While no health emergency was declared, Rome authorities urged residents to close their windows and stay indoors. City hall also recommended Romans avoid eating produce cultivated near the plant going forward, suggesting fears of toxic residue settling in the northern part of the city.

Authorities were scrambling not only to monitor the smoke cloud but to find an alternative plant for both regular garbage treatment and to deal with the Christmas holidays, when trash collection spikes.

The Salaria facility treats about 800 tons of garbage a day — between 20 and 25 percent of the city total, news reports said. Rome's garbage collection and disposal system were notoriously insufficient even before the plant went out of service, and officials acknowledged that the blaze turned a festering problem into an emergency.

Mayor Virginia Raggi appealed for local authorities in Lazio and other regions to lend a hand and open up their depots to Rome's trash for the foreseeable future.

"All institutions are working to facilitate a solution," she said at a news conference that was interrupted by hecklers.

Environment Minister Sergio Costa said health authorities have determined that there is no immediate health emergency due to the smoke, but he said the situation is being monitored.

He suggested foul play, noting that in recent days structural work had begun to improve the plant's functioning and capacity.

"It's perplexing that precisely at the moment that the problem was being dealt with ... a fire breaks out," he said.