A volcano on the Italian island of Stromboli erupted dramatically on Wednesday, reportedly killing a hiker and sending tourists fleeing.
The volcano is known to be active but on Wednesday there was a particularly powerful eruption.
Italian media reported that a hiker had been killed and their partner injured, but firefighters could not immediately confirm any casualties.
Rescue services said the eruption had started fires on the western side of the small Mediterranean island north of Sicily. Fire crews were being called in from nearby locations and a Canadair plane was already in action.
"We saw the explosion from the hotel. There was a loud roar," said Michela Favorito, who works in a hotel near Fico Grande, on the east side of the island.
"We plugged our ears and after this a cloud of ash swept over us. The whole sky is full of ash, a fairly large cloud," she told Reuters.
"It was like being in hell because of the rain of fire coming from the sky," Italian news agencies quoted local priest Giovanni Longo as saying.
Fiona Carter, a British tourist on the island of Panarea, some 27 km (17 miles) from Stromboli, heard the blast.
"We turned around to see a mushroom cloud coming from Stromboli. Everyone was in shock. Then red hot lava started running down the mountain towards the little village of Ginostra," she told Reuters.
"The cloud got bigger, white and gray. It enveloped Ginostra and now the cloud has covered Stromboli entirely. Several boats set off for Stromboli," she added.
Italy's National Institute of Geophysics and Volcanology (INGV) said there were two huge explosions on the central-southern side of the volcano's crater at around 1446 GMT Wednesday.
The explosions were preceded by lava spills "from all the active mouths of the crater terrace," the INGV said, prompting a two-kilometer high plume of smoke.
INGV expert Stefano Branca told Reuters there had been a "paroxysmal eruption" on the island, when high-pressure magma explodes from a shallow, underground reservoir. "These are events of great intensity and quite rare," he said.
A firefighting plane could not put out fires in the area because of the amount of smoke, Italian media reported.
The INGV said it was monitoring the situation.
Stromboli is part of the seven-island Aeolian Archipelago just off Sicily in southern Italy.
Tourists often climb to the 924-meter (3,000-foot) summit of the volcano and peer into its crater, with small puffs of molten rock regularly blasted into the sky.
According to the geology.com website, Stromboli is one of the most active volcanoes on the planet and has been erupting almost continuously since 1932.
The island was the setting for a 1950 movie starring Ingrid Bergman and, with other islands in the Aeolian archipelago, has become a favorite location in recent decades for holiday homes for the rich and famous.