PROVIDENCE, R.I. ? The dealer who sold soundproofing to the nightclub where an inferno killed 97 people said Friday the owners bought cheap and highly flammable packing foam, not real acoustic insulation.

Experts said the packing foam burns like gasoline and emits a dense, toxic smoke.

Store records show The Station club purchased “the lowest grade, the cheapest stuff,” said the dealer, Aram DerManouelian, president of American Foam Corp. “They had choices and that’s what they bought.”

An attorney for co-owner Jeffrey Derderian wouldn’t comment on the purchase and an attorney for his brother and co-owner Michael Derderian didn’t return calls.

Investigators visited American Foam’s headquarters in Johnston this week and left with samples of the foam and an invoice for the sale of 25 sheets of low-density, polyurethane packaging foam to The Station for $575, DerManouelian said. He said the company cut and sold the foam for use as packaging material.

Soundproofing has emerged as a central focus of the investigation into the Feb. 20 fire, one of the deadliest nightclub blazes in U.S. history. Authorities believe sparks from the pyrotechnics of the band Great White ignited soundproofing behind the stage, sending flames racing through the one-story wooden building in West Warwick.

A grand jury is investigating.

Maggie Cardinale of Narragansett, R.I., pauses by a grouping of wooden crosses hanging on a fence enclosing the burnt wreckage of The Station nightclub in West Warwick, R.I. Cardinale brought lilies Friday in remembrance of her friend, Lisa D'Andrea, who was among the dead. A 97th victim died early Friday from her injuries.

The June 2000 foam purchase came a few months after the Derderians bought the club, and followed complaints about noise. The invoice does not say who at the club ordered the foam, DerManouelian said.

“They asked for egg-crate material and that’s what we sold them,” he said. “It’s good packaging material. You just can’t light it on fire.” He said the store also sells fire-retardant packing foam, but “it costs about twice as much.”

Officials with the band maintain they had the club’s permission to set off the pyrotechnics; the club’s owners deny that.

Great White lead singer Jack Russell was subpoenaed to appear Friday before the grand jury. His lawyer, Neil Philbin, said Russell was seeking immunity from prosecution before testifying.

The death toll from the blaze rose to 97 after the death Friday of Linda Suffoletto, who had been in a Boston hospital since the fire. Her husband, Benjamin Suffoletto, 43, also was killed. About 50 people remained hospitalized, 34 in critical condition.