BOSTON (REUTERS) - Tamerlan Tsarnaev, the Boston Marathon bombing suspect killed in a shootout with police, had bought two large packages of fireworks in February from a store in Seabrook, New Hampshire, the company that runs the store said on Tuesday.
The amount of explosive powder in the purchased fireworks would not have been "anywhere near enough" to build the bombs used in the April 15 attack as they have been described publicly, said Mr William Weimer, vice-president at Phantom Fireworks. More potent powdered explosives could be readily obtained at a gun store, he said.
Tsarnaev asked the clerk behind the counter for help in choosing the largest fireworks available and selected the "Lock and Load" reloadable mortar unit on her suggestion, Mr Weimer said.
Tsarnaev paid US$200 (S$248) cash for one box containing 24 mortar shells and received a second box free under a store promotion, he said.
Tsarnaev and his younger brother, Dzhokhar Tsarnaev, are accused of planting two improvised explosive devices near the marathon finish line, killing three people and injuring 282.
The older Tsarnaev was killed on Thursday night. Dzhokhar Tsarnaev survived shootouts with police and was taken into custody the next day, and remains in "fair" condition at Beth Israel Deaconess Medical Center in Boston.
On Monday, Federal prosecutors filed two criminal counts against him for the bombings.
The brothers may have tried to extract explosive powder from the fireworks but would have discovered it was insufficient to fuel a bomb, Mr Weimer said. "They probably experimented with it and moved on," he said.
Phantom discovered the sale after the names of the suspected bombers were released and reported the details to the FBI, Mr Weimer said.
The sale of fireworks is legal in New Hampshire but not in Massachusetts, so many Bostonians travel to Phantom's Seabrook store to buy the devices, he said.
Faisal Shahzad, convicted of attempting to bomb Times Square in New York in 2010, used fireworks bought from another Phantom Fireworks store in part of his failed explosive device, Mr Weimer said.