AUCKLAND, Nov 26 - Emergency services were called to the blaze at a two-classroom block at Maungatere Alternative Education Centre in Rangiora at about 3am on Saturday.

As firefighters contained the fire that caused "extensive damage", another blaze was spotted at a shed on a neighbouring property, a Fire Service spokesman said.

Investigators were on the scene on Saturday morning and were treating both fires as suspicious, he said.

NZN