A man ran into the rectory of an Episcopal church in Maryland with his clothes on fire, causing a blaze which killed him and the church's pastor.
Investigators believe Mr John Sterner, 56, was covered in a flammable substance when he entered the building on Tuesday.
Reverend David Dingwall was stricken by smoke and heat when he went to save his computer on the second floor of the burning building.
He died in hospital.
A church volunteer was left badly burned after Mr Sterner bear-hugged her and set her clothes alight.
The woman, who has yet to be identified, is being treated at a burns unit in a Baltimore hospital.
Another priest, Reverend Heather Cook, told AP: "This is just such a bizarre incident. It's bad enough to lose somebody, but right before Thanksgiving through a bizarre kind of fire. People are stunned. It's not just the parish, it's the whole community."
A rectory, or clergy house, is the residence, or former residence, of one or more priests. These homes are typically owned and maintained by a church as a benefit to its clergy.
There was little damage to the church itself from the fire.