Updates Below Police and firefighters are on scene in the East Village at the site of a major building collapse. The FDNY confirmed that the collapse occurred at 125 2nd Avenue near E 7th Street around 3:15 p.m. There are preliminary reports of injuries, but we'll update as we learn more information. Update: Here's video from the moment of the blast.

Update: The FDNY has now confirmed there are multiple injuries at the scene. The residential building has a nail salon (E-Nail) and a women's clothing store (Enz's); it is right next door to vegetarian mainstay B&H Dairy.

According to the Department of Buildings, there was a stop-work order on the property in 2004.

Update: The FDNY has confirmed that the neighboring building is also engulfed in flames. They confirmed there is at least one person who has been critically injured; the NY Post is now reporting that "as many as 30 people" are injured at the scene.

Second Avenue is now closed from E 14th Street to Houston, according to police.

According to various people at the scene, the second building (which is reportedly 121 2nd Avenue) has collapsed completely. That building contains Sushi Park; Eater reports that Sushi Park was destroyed, and now the same is true for the neighboring Pommes Frittes.

Here is a video of the fire from down the block:

And here's video of the fire from a neighboring building:

And one from right below:

Update: FDNY say that over 200 firefighters and over 45 units have responded to the 7-alarm fire. At least two people with critical injuries have been taken to Bellevue Hospital. They add that 123 2nd Avenue has collapsed, and they are still fighting the blaze at 121 2nd Avenue; our reporter there tells us that the "building exterior appears to be holding up. Surrounded by a ton of smoke right now."

Cops at the scene also tell us that the fire may have been caused by a gas explosion. The crowd is being moved down to Houston because according to one cop, "they don't know what's going on and there's a chance the building will collapse."

Several witnesses described the explosion to us. "I heard it from 12th Avenue," said 52-year-old David Vincent. "I thought maybe someone had dropped something from a truck, it had that metal sound. The restaurant, the whole front was blown off."

Seth Tillett, 59, said: "I ran down the street when I heard. I saw two people covered in glass and blood. One man and a woman, she obviously got the blast and looked in shock." Susan, a 40-year resident of the area, added, "It was horrible, I was in a store on 6th St and it sounded like a bomb."

Update: According to ABC, there are 12 injuries at the scene, including 4 critical injuries. Francis X. Gribbon, the chief spokesman for the FDNY, told the Times what the cop on the ground told us: "It was probably a gas thing, it looks like," he said. "But that’s not confirmed."

Witnesses tell ABC 7 they smelled a strong odor associated with gas before the explosion. The smell from the fire has spread to Midtown and western Brooklyn.

The NYPD now tells CBS that crews were working on the gas line in the area when the explosion happened. According to the Post, a diner at Sushi Park at 121 2nd Avenue told cops he heard an explosion inside the kitchen.

Troy Hinson, a 37-year-old East Village local, took some of the dramatic photos above, and was shaken after the explosion: "I was going to yoga on St Marks. I was going to eat sushi at that place. I said goodbye to my friend, and it happened."

Another local, 31-year-old Andrew, added: "I was working from home, the explosion shook my building and it scared the crap out of me. The bottom couple floors collapsed on the sidewalk in a pile of debris...The flames were 300 feet high."

Update: Witness Chris Mosier had just finished eating at B&H and was crossing 2nd Avenue at 8th Street when he felt a huge boom: "I looked back and just saw people running on the street, like nobody was running from the restaurant, just bystanders running out of the way," he told us. "And when i looked back it was like the first two floors of the building, like the face had kind of blown off. So I called 911 and people started to gather pretty instantly, there was a huge scene of people before police showed up."

He observed a woman come out of a fourth floor window and climb down the fire escape as other people helped her down at the bottom. Other people were wandering around in the rubble of Sushi Park. He added:

When I ran over, there was a man who had been either blown off the sidewalk or out of the building, maybe from the second floor, but I don't know. Blood by his head, and as I ran over there were three or four bystanders who were picking him up and carrying him across the street. And he was totally unconscious. They took him over by a car straight across the street. At that point there was no movement or no one moving out of the first floor of that restaurant. My assumption was when I ran over there that people were probably trapped under some of the building that had fallen forward. I didn't see anybody there, I didn't see any movement.

Here's another view of the actual collapse:

Video shows East Village building collapsing after explosion and intense fire. (courtesy of Daniel Berkowitz.)Watch updates LIVE on NY1: http://bit.ly/1ACyxrg

Posted by NY1 on Thursday, March 26, 2015

According to the NYPD Community Affairs Twitter, "Building Explosion update: Displacement shelter has been setup at PS 63 located at 121 East 3rd street. @RedCross is available at scene."

Update: Mayor de Blasio is addressing the media at a press conference at the site: "The explosion here in the East Village affected four buildings," he said, identifying them as 119, 121, 123 and 125 2nd Avenue. "The actual explosion occurred at 121, which caused it to partially collapse, and 123 collapsed as well. Preliminary evidence suggests this was a gas-related explosion—that investigation is ongoing. The initial impact appears to have been caused by plumbing and gas work that was occurring at 121 2nd Ave."

"We are praying that no other individuals are found injured and that there are no fatalities," he said.

He added that the FDNY and first responders were able to contain the fire to those four buildings. He also reiterated that 12 individuals had been confirmed injured, three of them critically. Two of those people critically injured have burns to their airways, and the third has smoke inhalation.

De Blasio confirmed that Con Ed was at the building around 2 p.m. for separate reasons, they "found the work to be unacceptable," and gave instructions about what needed to be done. The explosion happened about an hour later. "Until we know what happened here we cannot pass judgement," de Blasio emphasized about the investigation into the cause of the fire.

"Any time you smell gas, you need to call 911 immediately, or call Con Edison immediately," de Blasio said at the end of the presser.

FDNY Commissioner Daniel Nigro said the call about the explosion came in at 3:17 p.m., and the FDNY had a three minute response time. "They were not expecting this scene," he said. "The first 15 minutes [firefighters] made extremely dangerous searches of these buildings." He said that 119 is a fully-involved fire, and still in danger of possible collapse.

"We will be here for a very long night," Nigro added.

Additional reporting by Jessica Warriner and Rebecca Fishbein