CEDAR FALLS, Iowa (AP) -- Authorities say a little Iowa boy who heard a smoke alarm awakened his mom so the family could flee a fire at their home in Cedar Falls.

The Cedar Falls fire department says 4-year-old Rylee ran into his parents' room a little after 6 a.m. Thursday and roused his mother, Ashley Hannan. She went into his room and saw smoke and flames coming from a wall of the mobile home.

The department says Hannan, her fiance, the 4-year-old and their other son then fled to safety outside. No injuries have been reported.

The fire cause is being investigated.