BALTIMORE — A natural gas explosion destroyed three row houses in Baltimore on Monday, killing a woman and trapping other people in the wreckage. At least six people were seriously injured, and firefighters were searching for more survivors.

Dozens of firefighters converged on the piles of rubble. A fourth house in the row was ripped open, and windows were shattered in nearby homes, leaving the northwest Baltimore neighborhood of Reisterstown Station strewn with debris and glass.

“It’s a disaster. It’s a mess. It’s unbelievable,” said Diane Glover, who lives across the street. The morning explosion shattered her windows and blew open her front door, bending the frame. “I’m still shaken up,” she said hours later.

Six people were hospitalized, while a woman was pronounced dead at the scene, a fire spokeswoman said. Rescuers were painstakingly going through the wreckage by hand.

“We’re prepared to be here throughout the night and as long as it takes,” Baltimore Fire Department spokeswoman Blair Adams said during an afternoon news conference. “We’re trying to make sure that we comb through every area to determine if there are any victims inside.”

While the cause wasn’t immediately clear, The Baltimore Sun reported last year that dangerous gas leaks have become much more frequent, with nearly two dozen discovered each day on average, according to the utility’s reports to federal authorities. The Baltimore Gas and Electric Co. has thousands of miles of obsolete pipes that need to be replaced, an effort that would cost nearly $1 billion and take two decades, the newspaper said.

BGE spokeswoman Linda Foy said Monday afternoon that the utility was still working to shut off a gas main in the area.

“Once we make the area safe, we can then begin to make repairs and to also understand what happened,” Foy said.

Glover, 56, and her 77-year-old father, Moses Glover, were at home when the massive explosion shook their house, knocking over a fan and some of her DVDs.

“I jumped up to see what was going on. I looked out the bathroom window and there was a house on the ground,” she said. “It sounded like a bomb went off.”

Dean Jones, 36, who lives nearby, said he ran to the scene and saw a mess of bricks, glass and cinder blocks. But he also saw a box of pancakes.

“You could tell this was a house that people lived in,” he said.

Jones said he and others began calling out for survivors and were able to locate an older woman who firefighters eventually pulled out. Kevin Matthews, who lives on the block, told The Baltimore Sun that he could hear trapped children shouting: “Come get us! We’re stuck!”

Barry Leventhal, whose warehouse equipment business is about 150 feet from the blast site, said he was in his warehouse when the explosion erupted and shook his building, damaging lights and a concrete wall.

Leventhal ran into an office to check on his son-in-law. Fortunately, none of the company’s 10 employees were injured.

“We thought a plane crashed or something. We couldn’t figure it out,” said Leventhal, the owner of Everything Warehouse.

BGE asked the Maryland Public Service Commission to approve a new gas system infrastructure and a cost recovery mechanism in late 2017 to pay for upgrades.

“Founded in 1816, BGE is the oldest gas distribution company in the nation. Like many older gas systems, a larger portion of its gas main and services infrastructure consists of cast iron and bare steel – materials that are obsolete and susceptible to failure with age," the PSC wrote in a 2018 order approving a modernization plan.

When aging pipes fail, then tend to make headlines. Last year, a gas explosion ripped the façade off a Maryland office complex in Columbia, affecting more than 20 businesses. No one was injured in the explosion, which happened early on a Sunday morning. In 2016, a gas main break forced the evacuation of the Baltimore County Circuit Courthouse. Under Armour Inc. had to evacuate its Baltimore office after a gas main break in 2012.

Baltimore City Council President Brandon Scott said he needs “the entire city of Baltimore right now to focus on hopeful prayers for those individuals that have been impacted by this.”

“I want everybody in the city really to rally around those individuals that are still fighting for their lives,” he said at a news conference.

Associated Press contributors include Mike Kunzelman in Silver Spring, Brian Witte in Annapolis, and Ben Finley in Norfolk, Virginia.