Salt Lake fire officials are investigating a string of suspicious fires Wednesday night.

At 4:47 p.m. a car fire broke out at 425 E. 21st South, and then a half hour later another fire was sparked in a field at 21st South and I-15. Minutes later a house once used as a business caught fire at 522 E. 21st South, according to fire officials.The 21st South fire "appears suspicious, but it is still under investigation," said Capt. Joe D. Campbell. He said the blaze, which originated on three floors of the building, caused about $10,000 damage, including considerable smoke damage.

"We were worried that the roof might cave in," he said.

A similar fire burned an attorney's office in an old home at 1343 S. 11th East at 10:17 p.m. It was the second fire in the structure within five months. The first fire was in December.

"The fire started in the basement. There are suspicious circumstances. There wasn't much fire damage, just water damage and smoke," said Capt. Gary Kraus.

No damage estimate was available.

One of the building's owners said renovation of the home from the last fire was just under way. The blaze caused between $38,000 and $48,000 damage.

Kraus said the building was unlocked at the time of the fire.