PORTLAND, Ore. (AP) — Fireworks caused a deadly Fourth of July blaze at an apartment complex in northeast Portland, authorities said.

Portland Fire & Rescue said in a statement Thursday that the investigation into the large blaze is still open.

Robert William Gremillion and Seth Robert Thompson, both 31, died and six other people were hurt, including a 25-year-old woman who remained hospitalized Thursday in “critical but stable condition,” fire officials said.

Gremillion and Thompson were roommates in a top-floor unit and friends from Louisiana who worked together developing computer games, The Oregonian/OregonLive reported.

Residents, many of whom jumped from windows or balconies, told the newspaper that they first saw flames in a dumpster in the carport under the apartments. Several said they heard fireworks before the fire started around 3:30 a.m. July 4.

Witnesses said Thompson jumped from the porch and that neighbors tried to help him once he was on the ground. Other residents said they encouraged Gremillion to jump but he didn’t.

The hospitalized woman and Thompson were a couple, according to police and residents. Her name hasn’t been released.

Portland officials had banned the sale and use of fireworks a few days before the holiday because of hot, dry conditions.