BLACK JACK, Mo. (AP) — Two men have been charged with murder in a house explosion near St. Louis that authorities say killed four people who were assembling fireworks in a garage.

St. Louis County prosecutors charged 37-year-old Terrell Cooks and 43-year-old Seneca Mahan with three counts of second-degree murder before a fourth victim died Saturday.

Prosecutors said Cooks admitted that he and Mahan made explosive devices designed to make a loud bang and bright flash and sell them to others.

He directed younger people to load canisters with explosives and attach a fuse for lighting. It wasn’t immediately clear whether the two men had attorneys who could comment for them.

They are being held on $350,000 bail.