Rep. Seth Moulton, (D-MA) is calling for an explanation after a series of explosions in the Merrimack Valley caused mass displacement, injuries, and the death of one 18 year-old man.

“The fundamental responsibility of a gas company — of any company, frankly, should be to keep its customers safe,” Moulton said during an interview with Boston Public Radio Monday. “...the gas company failed to meet that basic test.”

Moulton, along with Rep. Niki Tsongas (D-MA) and Senators Elizabeth Warren (D-MA) and Edward Markey (D-MA) penned a letter to the president of Columbia Gas of Massachusetts, demanding clarity in the wake of the incident.

“Thoughts and prayers are not enough,” the letter reads. “The residents of Lawrence, Andover, and North Andover want answers, and they deserve them. As local, state, and federal partners continue to gather information and assist those in need of food, water, shelter, and medical care, we hope that you will provide much-needed clarity as to how this incident happened and how Columbia Gas will prevent a similar event from occurring in the future.”

Moulton told WGBH News he spoke with the CEO of Columbia Gas in a phone conversation over the weekend. “I finally got a call back from the CEO on Saturday night, I think I spoke to him at about 10:30 on Saturday night. He was very polite and whatnot, but it still sounds like they’re out to lunch and don’t really understand the magnitude of this crisis,” Moulton said. “He didn’t even acknowledge that a young man lost his life in the course of our conversation.”

Moulton said he noted concerns with the fact that the company took hours to respond to customers. “His answer to me was, ‘well I’m sorry that you’re frustrated that it took awhile to make a public announcement, but we were available to our customers,’” Moulton said. “I said ‘what do you mean by that?’ and he said ‘we were in contact with our customers when they needed it...our customer service center was operational.’”

“So I guess that means that if your house blew up, and you walked outside and saw it on fire, you could call the gas company’s customer service line, and they might respond to your request,” Moulton continued. “It’s so pathetic, it’s just unbelievable.”

The National Transportation Safety Board is currently conducting a federal investigation into the incident.

“We have to understand why this happened in the first place, and then we really want to know why it took five hours after the first explosion took place for the gas company to even acknowledge, publicly, that something was going on, let along tell residents how to be safe,” Moulton said.

“Thank god we have amazing first responders on the ground, the state and local police, Red Cross volunteers who set up shelters, and the local authorities who helped people get out of their homes,” Moulton continued. “If we hadn’t had that evacuation, I’m confident more people would have been killed.”

Columbia Gas has not responded to a request for comment.

To hear Rep. Seth Moulton’s full interview with Boston Public Radio, click on the audio player above.