Investigators announced on Thursday that the cause of the fire at The West Fertilizer Co. plant is still undetermined, although they believe they have narrowed it to three scenarios.

On April 17, the fire caused large quantities of ammonium nitrate to explode in two blasts that were felt from miles away. Fifteen people died as a result of the explosions, most of which were first responders to the catastrophe. Numerous houses were damaged, as well as two of the city’s schools.

Although investigators have ruled out several possibilities, they have yet to pinpoint the cause of the fire. Investigators are still exploring whether it was intentionally started in a criminal act. They also say that a spark from a golf cart, which had previously been recalled by its manufacturer and is believed to have been parked in the room where the fire began, could have been what started it. The fire could also have resulted from a problem with the plant’s electrical system.

The Christian community in West, Tx. has begun serving families who were affected by the tragedy in several ways. St. Mary’s Catholic Church held the funeral service for all of the first responders, regardless of whether the deceased were Catholic in denomination.

According to an office worker at the church, roughly ninety percent of those injured and about eighty percent of those that died were members of their parish. St. Mary’s is hosting prayer sessions in the community, and is working with the widows of the deceased to find healing.

The pastor of First Baptist Church is living in a motel as a result of the explosion. His congregation is offering three meals a day, showers, and laundry service to those in need. A church receptionist said that certain congregation members’ houses were “totally demolished,” and that some who sustained damage were underinsured.

The church is organizing a service project in mid-June called “Love West Volunteer Week.” Their website urges people to pray for those affected. “Although this tragedy is a terrible experience and has been absolutely horrific, we have a peace that doesn’t make sense and our strength is renewed day by day,” it says.