A Long Island man says he was burned by an e-cigarette battery inside his pocket while inside a Home Depot store on Monday, days after a New York City woman says she was injured in a similar scenario.

Stephen Rosenbluth was shopping inside the store in Freeport when the battery ripped through his sweatpants and boxers.

"My pocket went on fire, it actually exploded," he said.

Rosenbluth said other shoppers were stunned and apparently thought he was trying to blow up the store until they realized his pants were on fire.

Patricia Mills, who was in line behind Rosenbluth, said, "He went into his pocket, and it [blew up] like a firework."

"It was very frightening," she said.

Rosenbluth said the explosion left second-degree burns on his hand and thigh. When he tried to pull the battery out, "I took a paper towel, wiped it and some of my skin came off."

Other than email the cigarette manufacturer, Rosenbluth said he almost let the incident slide until he saw NBC 4 New York's report on Katrina Williams, whose rechargeable e-cigarette battery exploded in her pocket earlier this month.

Efest, the China-based company that made the battery, said in an email that the company's battery packing boxes contain a warning to customers. Beginning this year the warning is being printed on the battery wraps as well, the email said.

A warning on the company's website states that batteries shouldn't be placed in pockets. Also on the website is a 2014 email from a customer who appeared to have a similar experience, reading, "I was only informing you of the hazards of keeping the battery in your pocket in hopes that you put a warning on the battery so that the same thing doesn't happen to anyone else."

"We are so sorry about this customer. ... But the vaping customers also (have) the responsibility to know how" to use their equipment, the company's email said

Rosenbluth's lawyer says there's no warning on his client's batteries. That's a problem that needs to be fixed, he says.

"Was this substandard manufacturing, is this a problem with all lithium ion batteries?" said attorney Keith Altman. "We don't know who, but one body has to regulate."

With the increasing popularity of electronic cigarettes have come reports of exploding e-cigarette batteries. The U.S. Fire Administration estimated more than 2.5 million Americans used e-cigarettes in 2014, and between 2009 and 2014, there have been 25 fires or explosions involving vaporizer batteries.

Sean Kane, president of Safety Research & Strategies, Inc., told NBC News he is "troubled" that no federal agency is regulating e-cigarettes.

"We're seeing a flood of these low-cost, low-quality devices that are hurting people and we're dealing with safety as an afterthought," Kane said. "We need tough standards that require good design and manufacturing practices to ensure these devices are produced safely."