CHULA VISTA, Calif. -- An investigation was underway Thursday to determine what caused two brush fires that broke out in Chula Vista Wednesday night.
The first one was reported around 8 p.m. off Interstate 805 and burned about half an acre. The second one started just before 10:20 p.m. near a riverbed around Hollister Street and burned about four acres.
"We pretty much threw all resources at it," said Linda D'Orsi with the Chula Vista Fire Department. "We had a combined effort with the City of Chula Vista, Imperial Beach and the City of San Diego."
Two helicopters were used to attack the fire, which D'Orsi told FOX 5 is rarely done at night. "This was new," D'Orsi said. "When I heard we were having helicopter drops I questioned it as well. And it was decided to provide that service. I believe it was predetermined because of the Red Flag warning and the weather."
The flames could be seen from homes in a nearby neighborhood.
"My mom was freaking out but I kept telling her, 'Calm down, everything's going to be okay,'" said Maria Guerrero, who watched the fire burn from her house. "It got really intense for like 15 to 20 minutes, but that's when they started dropping water."
Chula Vista police said both fires broke out near homeless encampments, which are a suspected source. Police told FOX 5 the encampments are a concern and that they have a homeless outreach team that specifically targets those areas.
"These officers assigned to the team go out with these services and proactively go into these encampments, offer services, look for maybe some bad actors that might be in there preying on other homeless individuals," Lt. Dan Peak said. "If these people are in fact committing crimes they will be arrested."
The causes of the fires remain under investigation.