SANTA MARIA, Brazil — Penny-pinching by a band known for its onstage pyrotechnic displays may have cost more than 230 people their lives at a nightclub in southern Brazil, according to a police inspector leading the investigation into the deadly blaze.

Marcelo Arigony said Tuesday that members of the band knowingly purchased flares meant for outdoor use because they cost a mere $1.25 a piece, compared with the $35 price tag for an indoor flare.