The main building on Dalhousie University’s Agricultural Campus is closed to students and staff after fire crews responded to a stubborn blaze Wednesday evening.

Emergency crews were called to the Cox Institute of Agricultural Technology in Bible Hill, N.S., around 9:30 p.m. Wednesday.

Several fire departments from surrounding communities responded to the scene.

Truro Fire Chief Blois Curry said the fire was mainly on the roof and started to spread down to the third floor.

No injuries were reported.

David Gray, the dean and campus principal, says the fire was finally extinguished around 4 a.m., but there's no assessment yet of damage or the cause.

The university says the Cox Institute will be closed until further notice as the fire marshal conducts an investigation.

Faculty and staff affected by the fire are asked to report to work in the MacRae Library or make alternative arrangements with their supervisor.

The university says some summer classes will also be held in the MacRae Library.

According to Dalhousie University’s website, repairs to the roof of the building have been ongoing since May 22.

With files from The Canadian Press and Bell Media's Big Dog 100.9