The moment of the explosion, which began shortly at 4:46 pm local time on Wednesday, was captured on camera by visiting tourists.
A view of the explosion captured by Twitter user Fiona Carter. Photo: @FionaCarter/AFP
Smoke poured out of the volcano and two kilometres into the air, while lava poured from the crater.
One local resident said there was a “rain of fire coming from the sky”.
One hiker, identified as an Italian man from Sicily in his 30s, was found dead. His companion, from Brazil, was discovered in a state of shock.
An image shared by Mario Calabresi on Twitter. Photo: @mariocalabresi/AFP
The burning debris caused fires around the tiny village of Ginostra. Some tourists reportedly fled into the sea to avoid the smoke and flames.
Fires around the crater, pictured by Mario Calabresi. Photo: @mariocalabresi/AFP
The thick clouds of smoke made it difficult for firefighters to fly overhead and dump water onto the slopes.
A Canadair firefighting plane in the smoke. Photo: Giovanni Isolino/AFP
Parts of the island were evacuated and beaches were closed as a precaution.
Most of the fires had been put out by Thursday morning, while a huge cloud of ash hung over the island.
Early morning on Panarea. The day after Stromboli erupted. Volcanic ash everywhere on the sky. pic.twitter.com/rw0lNJlYMU
— Fiona Carter (@FionaCarter) July 4, 2019
Immensa nube di cenere. Il vento la porta verso le altre Eolie e la Sicilia pic.twitter.com/9D9h1tCp7S
— mario calabresi (@mariocalabresi) July 3, 2019
“It's been a long time since we had an eruption of this magnitude,” former local councillor Gianluca Giuffre told Rai News.
A view of houses near the volcano. Photo: Giovanni Isolino/AFP
The last major eruption on Stromboli was in 2002, when six people were injured and falling magma created a tidal wave that swept away piers and boats. The island was closed to visitors for more than a month following the explosion.
Smaller eruptions took place in 2003, 2007 and between 2013-14.
Stromboli erupts in August 2014. Photo: Giovanni Isolino/AFP
The 2014 eruption sparked a spike in tourist numbers. Even though the volcano was temporarily closed to hikers, visitors flocked to watch lava flow into the Mediterranean from the comfort of their boats.
Sunbathers get a view of the eruption in August 2014. Photo: Giovanni Isolino/AFP
Stromboli is one of three active volcanoes in Italy, and among the most active in the world. It has been erupting almost continuously for most of the past 85 years.
Geologists even coined a term, “Strombolian”, to describe the distinctive type of eruption with which the volcano is associated: series of mild but spectacular bursts that send molten rock and ash shooting into the air as high as hundreds of metres.
Stromboli's eruptions can be seen from far and wide, especially at night, leading some to dub it the “lighthouse of the Mediterranean”.