The North Carolina Department of Labor has issued more than $21,000 in fines to three companies involved in the fatal gas explosion in Durham earlier this year.

News outlets report PSNC Energy and two subcontractors were cited for the April 10 explosion in Durham that killed two people, injured 25 and destroyed buildings.

Optic Cable Technology was fined $14,000 for two safety violations. An earlier report from the Durham Fire Department determined an Optic crew boring for fiber optic cable hit the line and caused the leak. The Department of Labor says Optic didn’t locate underground pipes before drilling and didn’t immediately call authorities after the gas line ruptured.

PS Splicing LLC was fined $2,100 for not performing regular inspections of the site.

PSNC, part of Dominion Energy, was fined $5,000 for “ineffective response procedures.” The department says the responding employee wasn’t wearing protective gear and parked his vehicle near the leak.

The utility says they disagree with the findings.

Coffee shop owner Kong Lee was killed in the blast, while the other victim was Jay Rambeaut, a Dominion Energy first responder, who died 15 days later from his injuries.