At least four people were injured and some feared dead following an explosion and fire at a Dallas apartment building that set plumes of black smoke into the air, authorities said.

Dallas Fire Deputy Chief Mark Berry confirmed there were fatalities in the explosion but was unable to say how many.

The incident was reported around 12:50 p.m. at a two-story apartment complex in the city's Oak Cliff neighborhood amid reports of a gas leak, Dallas Fire-Rescue Assistant Chief James Ross told reporters at a news conference. Nearly 100 firefighters responded to the scene.

"The fire is contained, but our members are still working on the scene to do primary searches. We put a drone in the air to canvas the area to see if we have any, if we see any victims or anything around," said Ross. "At this time, it's unknown how many possible fatalities we may have."

Four people were taken to a hospital, but the extent of their injuries was not immediately clear.

People in the area reported hearing an explosion before the fire, but the exact cause of the blaze was unknown. In addition, windows on neighboring buildings appeared to be blown out and debris was scattered across the street. 

"I was chilling in my living room and bam, loud explosion. I mean, what I now know to be an explosion. But I thought a car ran into my house was my guess," Mike Sirois, who lives nearby, told FOX 4. "My dogs went nuts. I started to kind of check in just through the windows. I'm like, ‘What the hell was that?’"

"I walked outside and then some of my neighbors were already outside kind of looking to the east from Bishop Arts District and there was a massive plume of smoke," he added. 

Dallas radio personality Hawkeye, from Hawkeye in the Morning on 96.3, was also in the area at the time. 

"I just saw the flames, the smoke. You can see the smoke from about two miles away," he said. "I didn't hear the explosion, but I will tell you there are a number of ambulances here. I mean a ton of them here."

It was not clear how many people were in the building at the time. Fox News Digital has reached out to Dallas Fire-Rescue. A large plume of black smoke could be seen above the fire.

Dallas Mayor Eric Johnson encouraged everyone to pray for those impacted by the fire. 

"We ask everyone to please pray for our Dallas Fire-Rescue personnel who are still fighting this fire," he wrote on X. "They do an amazing job under very, very difficult circumstances like this. And we just pray that they will be safe while they try to save and help every single person they can affected by this," said Dallas Mayor Eric Johnson.

A family reunification point has been set up at Adamson High School, the city said.