A criminal indictment related to the deadly explosion at a central Greece cookie plant, which claimed the life of five female workers employed on the “graveyard shift”, has been upgraded to homicide with the possibility of intent.

Previously charges of involuntary homicide had been filed against the owner of the Violanta plant near the city of Trikala, the production director and the shift manager. In a subsequent development, the owner of the plant was subsequently arrested on Saturday afternoon.

According to a report in ERTnews, the charges were upgraded after arson investigators’ findings at the site.

The trio continues to face bodily harm charges.

Initial reports point to accumulated gas from leaks in an underground pipeline as causing the early morning blast and subsequent fire in late January.

Sources that spoke to the news media said repeated complaints, beginning five months ago, of gas in the air were not properly investigated. The same sources said an expert summoned to the site left without resolving the problem after clashing with the company’s management over his fee.