(CNN) -- Police and fire officials in San Jose, California, are asking for the public's help to find the person responsible for setting roughly a dozen fires in the downtown area.
Multiple fires were lit over several nights last week between 2 a.m. and 6 a.m., according to San Jose police, which released a statement and sketch of the suspect. No one was reported injured.
"These fires were very serious in nature and had the potential to cause serious injury or loss of life to both residents and firefighters," the statement read.
Of the 10 fires set last week, five had residents inside when the blazes began, said Fire Capt. Christopher Murphy. Most were started on the outsides of the structures, which were downtown or south of downtown.
Some structures were destroyed while others suffered minor to moderate damage. Eight of the 10 fires were set intentionally, while two remain under investigation, Murphy said.
Firefighters responded Sunday to three more suspicious fires, which may have been set by the same suspected arsonist, CNN affiliate KGO reported.
"We want to make sure people clear out anything that's flammable from their front yards, and we want to make sure everybody sees the sketch of the suspect," said San Jose Councilmember Sam Liccardo, according to KGO. "And we want to make sure that everyone who needs a fire alarm or batteries can get a fire alarm or batteries. We can supply it."
A $10,000 reward is being offered for information leading to the arrest and conviction of the person or people responsible for the fires.
CNN's Janet DiGiacomo contributed to this report.