NEW YORK (AFP) - Nineteen people were hurt Thursday when three New York buildings collapsed and a blaze tore through another in what preliminary indications suggested was a gas-related explosion.
Four people were critically injured after the blast ripped through a commercial and residential building in the popular East Village and then partly collapsed, triggering the collapse of the next-door building, the partial collapse of another and a huge blaze.
Dramatic cell phone footage broadcast by TV channel PIX11 showed panicked people running in fear from a sushi restaurant after the explosion.
"What happened? Oh my God!" one woman is heard yelling. Bystanders bend over a person lying amid debris.
Witnesses several blocks away described hearing a loud bang and thick smoke could be seen wafting high over the Manhattan skyline.
"It was crazy loud. The windows were shaking," said Philip McElroy, a 23-year-old student, who was visiting a friend two blocks away.
"There was a lot of smoke and part of the building was blown out."
New York Mayor Bill de Blasio said the initial impact appeared to have been caused by plumbing and gas work at the site.
The incident quickly heightened safety fears, a year after eight people were killed when a gas explosion levelled two apartment buildings in East Harlem in northern Manhattan on March 12, 2014.
"Our thoughts, our prayers are with everyone of them (the casualties) and of course we are praying that no other individuals are found injured and that there are no fatalities," de Blasio told a news conference.
A fire department spokesman raised the number of casualties from 12 to 19, including four people in a critical condition.
The department said 121 Second Avenue, scene of the initial explosion, partially collapsed, as did another building, while 123 Second Avenue went entirely and fire ravaged a fourth property.
Pommes Frites, a shop selling Belgian-style fries at 123 Second Avenue, said on Twitter it was closed until further notice due to "severe damage," but said its staff and customers were safe.
More than five hours after the incident, over 200 fire fighters were still working to control pockets of fire, the fire department said.
The Red Cross set up an emergency site in a school to support those made homeless, as well as neighbours and family members, de Blasio said.
Thick smoke filled the street and emergency workers shut down six blocks on Second Avenue, said an AFP reporter at the scene.
Fire Commissioner Daniel Nigro said staff were on the spot three minutes after the 3:17 pm emergency call.
The front of 121 Second Avenue was blown across the street and fire officers performed "extremely dangerous" searches of 123 and 121, he said.
The smell of burning drifted as far as Midtown Manhattan, around 40 blocks farther north.
Isaiah Barr, who was listening to music at home several blocks away when he felt a boom, said: "I was really scared." Authorities advised New Yorkers to stay at home and keep their windows closed to avoid the affects of smoke exposure.
The East Village is one of the most popular areas of New York, home to a large number of students and wealthy professionals, and stuffed with boutiques, restaurants, nightclubs and cafes.
Of those critically injured, two have burns to their airways and a third person fell unconscious after the blast, officials said.
One East Village hotel offered on Twitter three free nights stay to residents in the immediate vicinity of the affected area on Second Avenue.
De Blasio urged people not to speculate until the investigation had been completed but reminded New York's 8.4 million residents to act quickly if they smell gas.
"I will take this occasion to say, as we said many times after the East Harlem tragedy, any time you smell gas you need to call 911 or call (energy company) Con Edison immediately," he said.