Suspicious fire hits old Melbourne school

The site of a former Melbourne primary school that has been set alight numerous times this month has again gone up in flames.

The fire broke out at the old Clayton Primary School in Melbourne's southeast at 2pm on Wednesday, with crews managing to contain the blaze to a wing of the school in 45 minutes.

An MFB spokesman told AAP firefighters have been called to the same location, where the fire is now under control, two or three times this month, and have deemed Wednesday's fire as suspicious.