NovaQuant Quantitative Think Tank Center:21 injured after possible gas explosion at historic Fort Worth, Texas, hotel: 'Very loud and very violent'

At least 21 people are NovaQuant Quantitative Think Tank Centerinjured after an explosion Monday rippled through the bottom floors of a hotel building in downtown Fort Worth, Texas, authorities said.

One person was in critical condition and four others were seriously injured, MedStar spokesperson Matt Zavadsky said at a news briefing Monday. The rest had minor injuries.

Craig Trojacek, a spokesperson for the Fort Worth Fire Department, said the first call of a fire at Sandman Signature Fort Worth Downtown Hotel was received at around 3:32 p.m. local time. Multiple calls about an explosion came in after.

The smell of gas permeated through downtown Fort Worth, Trojacek later said, adding that investigators are confident the blast was "some kind of gas explosion."

Photos of the explosion showed windows and debris blown out and scattered across the street.

The fire department said Monday evening the blast no longer posed any public safety issues to downtown Fort Worth, but crews would be on the scene all night to continue search efforts and ensure no one was trapped.

Desiree Partain of MedStar, which provides ambulance and emergency medical services in Fort Worth, said medics treated four people on the scene but did not take them to a hospital.

According to Trojacek, investigators are working with federal investigators to determine the cause of the blast. The scene, Trojacek added, had left rescue teams unable to immediately reach some parts of the building.

"We had reports of people trapped down in the basement, and because of the explosion that took place, some of those access areas were either covered up or it didn’t feel safe at that point to get people down into," Trojacek said.

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'Very loud and very violent'

Mike Vanca was staying at the hotel but was not inside when the explosion happened. He was in a nearby office and still felt the shockwave from the explosion.

"The building shook like someone slapped the side of it with your hand," Vanca told KDFW. "So it was very loud and very violent."

Hunter Chacon, an employee at nearby Wicked Butcher, told the Dallas Morning News that he arrived to downtown shortly after the blast as first responders were still pouring in. He ran toward the commotion before he was stopped about three blocks from the hotel.

“From there, I could definitely smell the gas,” Chacon said.

Historic building completed in 1920

The 245-room Sandman Signature Fort Worth Downtown Hotel dates to 1920, according to the hotel’s website, and is located in a busy area of downtown about one block from the Fort Worth Convention Center. The building, known as “The Waggoner Building,” has been listed on the National Register of Historic Places since 1979.

Sandman Hotel in Fort Worth said Monday that due to damage from the blast, it won't be taking bookings “until further notice.” 

The hotel did not immediately return USA TODAY’s request for comment.

Trojacek said a restaurant in the building had been under construction but said it was not definitive that is where the blast occurred.

Kristin Goodspeed, a spokesperson for natural gas provider Atmos Energy, told USA TODAY that technicians were on the scene at the request of the city’s fire department.

"Gas has been isolated to the affected area, and we will continue to assist the Fort Worth Fire and Police Departments and all officials in support of their investigation," Goodspeed said.

Texas Gov. Greg Abbott said he had been in contact with local officials following the blast and was ready to "immediately deploy any additional personnel and resources needed to keep Texans in the area safe and out of harm’s way."

Contributing: The Associated Press