(AP) — Missouri Public Service Commission staff say in a report that Missouri Gas Energy failed to take “prompt and adequate” steps to ensure safety before a fatal restaurant explosion in Kansas City.

The 120-page report released Thursday says Missouri Gas Energy workers waited too long before checking whether gas levels had reached unsafe conditions inside JJ’s restaurant on Feb. 19, 2013. An explosion and fire leveled the building, killing a JJ’s employee and injuring more than a dozen people.

Authorities have said the explosion and fire were caused when a natural gas supply line was breached by a cable company’s subcontractor.

The PSC staff also filed a complaint against MGE asking the commission to find the utility violated the agency’s safety rules.

Officials with the utility declined immediate comment.