Bushfire forces Perth school evacuation

A bushfire that was deliberately lit could possibly threaten lives and homes in Perth's south, forcing the evacuation of a school.

The Department of Fire and Emergency Services has issued a watch and act alert for parts of Kensington, in the City of South Perth, after the fire was reported just after 1.30pm on Monday.

The West Australian Education Department said 45 students and about 40 staff had been evacuated from Kensington Secondary School.

Air support is helping ground crews to control the blaze, with local police saying its cause was deliberate.

Emergency services say the fire has been contained, but not controlled.