Updated

Prosecutors are declining to charge a 19-year-old who was suspected of starting two small fires in Southern California as blazes raged throughout the region last week.

The San Diego County district attorney's office said Tuesday that there was insufficient evidence to charge the man with starting the blazes. He and a 17-year-old boy were arrested in Escondido on Thursday on suspicion of arson in connection with fires that were extinguished within minutes.

The district attorney's office says it is prohibited by state law from providing information on the 17-year-old because he is a juvenile.

Investigators found no evidence linking the teens to about dozen wildfires that destroyed 44 houses, an 18-unit apartment complex and three businesses. The cause of the most destructive fires hasn't been determined.