Scott G. Winterton, Deseret Morning News
Salt Lake Fire investigator Wyman Berg begins the search for the cause in the aftermath of a fire in Salt Lake at 300 North and Marion Street (1040 west) Monday March 24,2008.

Salt Lake City fire investigators say a house that exploded this morning was the result of arson.

It's the second time in a year-and-a-half crews have responded to an arson-caused fire at that house. But investigators were unsure Monday morning if the same family lived in the house for each incident.

No one was injured in Monday's blast, although for awhile investigators did not know what had happened to the home owner. The two adults and a child who lived at the house were found safe about 2 p.m., said Salt Lake Fire Capt. Karleen Montanez. Investigators were scheduled to interview the adults Monday afternoon.

Officials say the family was not home at the time of the explosion, but it was unclear Monday where they were. Montanez also did not know where the family was found Monday afternoon.

Just before 3 a.m., a house near 300 North and 1040 West blew up.

"The north wall completely exploded off. The windows exploded out clear to the other side of the street. Glass was in the gutter on the other side of the street," Montanez said.

The fire also singed the siding off an adjacent home.

The nearest fire station was just a block away. The explosion woke the firefighters who got up to see what was happening. When they reached the house it was fully involved, Montanez said.

Initially, crews believed the house was vacant, she said. They discovered later, however, that a family had recently moved in. A family member showed up at the house later and told investigators he thought everyone was gone when the explosion happened, Montanez said. Firefighters also noted their were no vehicles parked at the residence.

An arson K-9 detected multiple "hits" of accelerants in the rubble of the heavily-damaged house. A neighbor reported to investigators seeing a car speed off just before the explosion.

In November of 2006 Montanez said there was another arson-caused fire at the same house. That blaze was smaller, she said.

Someone had recently broken into the garage of the house that blew up, Montanez said. There were also reports of car vandalism in the neighborhood.

Firefighters were working closely with police on the investigation.

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