B/C-7 had heavy fire in the first floor of a 2 story EOR dwelling, with extension to the 2nd floor. He also had reports of people trapped. He placed all hands in svc. Companies had 5 lines stretched and operating. Crews found 4 victims inside the dwelling, an adult female, a teen, and 2 young children ages 3 & 7. 1 teen escaped the blaze by climbing out a 2nd floor window to the roof.