A gas explosion rocked New York City's East Village on Thursday, critically injuring at least three people and causing three buildings to collapse, Mayor Bill de Blasio and Fire Department officials said.

A total of 19 people were injured, including four firefighters and one paramedic, said Ed Long, a Fire Department spokesman. None of those injuries was life-threatening, he said.

Speaking near the charred remains of two adjoining buildings on 2nd Avenue, De Blasio said that "preliminary evidence suggested a gas-related explosion."

"The initial impact appears to have been caused by plumbing and gas work that was occurring inside 121 2nd Ave.," De Blasio said.

Eleven buildings in the area of the explosion have been evacuated, Long said. It is unclear how many people have been displaced.

As of 10 p.m., firefighters were still putting out "hot spots," Long said.

Consolidated Edison President Craig Ivey told reporters at the scene that the company had workers at the building approximately one hour before the blast. They were conducting an inspection of a new gas meter that was being installed inside the building.

"The new installation did not pass our inspection at that time, meaning it wasn't ready for gas to be introduced," Ivey said.

The explosion comes one year after a gas-related blast leveled two buildings in East Harlem and left eight people dead. The March 2014 explosion occurred shortly after someone called the utility company to report a gas odor outside one of the buildings. The caller said the smell had also been present the night before.

Con Ed dispatched a team of investigators to the scene of the Harlem blast after the call was made, but it did not arrive in time.

In Thursday's explosion, De Blasio said a review of calls to Con Ed and 911 showed no one had called to complain of a gas odor in the East Village.

As of late afternoon, a New York Fire Department spokeswoman said that the building at 123 2nd Ave. had collapsed and that a fire was still burning at the building next door, which had been undergoing the plumbing and gas work. De Blasio said four buildings had been damaged in all.

Two of the people injured critically were taken to Bellevue Hospital, the Fire Department spokeswoman said. Among the other injured, five were being treated for non-life-threatening injuries at Mount Sinai Beth Israel, said David Slotnick, a spokesman for the hospital.

De Blasio said at an evening news conference that there were three people in critical condition; the Fire Department put the number at four.

Firefighters initially received reports of a building collapse around 3 p.m., according to the Fire Department. Images on social media showed a large smoke cloud and flames billowing from inside the structure's frame and from the roof.

Smoke was creeping into buildings throughout the area and obscuring views of the skyline, said Andrew Scott Taylor, who works for a public relations firm at 8th Avenue and 37th Street.

"We had a window that was really just about a sliver open in our conference room, and before you knew it the smell of smoke was everywhere. It was very potent," he told the Los Angeles Times.

The smoke was so thick, Taylor said, that the One World Trade Center tower was barely visible from the windows of his high-rise office building.

“Any time you see smoke, an obscene amount of smoke rising out of the skyline, it’s bound to be a little jarring,” he said.

About 250 firefighters battled the blaze, a department spokesman said.

The New York Police Department released aerial photographs of the scene.

Almost immediately after the fire began, images began to flood social media.

Major explosion on NW corner of 7th Street and 2nd Ave. Police here. pic.twitter.com/Xys9GBVzF4 — Scott Westerfeld (@ScottWesterfeld) March 26, 2015

Queally reported from Los Angeles. Susman reported from New York.

Staff writer Ryan Parker contributed to this report.

Follow @JamesQueallyLAT for breaking news.

UPDATES

9:59 p.m.: This story has been updated with information that two other buildings collapsed and 19 people were injured.

3:47 p.m. This story updated with comments from the president of Consolidated Edison in New York and a hospital spokesperson, as well as background on a deadly gas explosion in East Harlem last year.

2:58 p.m.This story updated with comments from Mayor Bill de Blasio.

2:25 p.m. This story updated with additional information from the Fire Department and an interview with an office worker in the area.

1:35 p.m.: This story updated with images released by the New York Police Department.

1:22 p.m.: This story updated with additional information from the New York City Fire Department.

The first version of this story was published at 12:59 p.m.