The CFA is on site to investigate.

A small number of staff members have reported feeling unwell and have been taken to hospital as a precaution.

Customers who visited the centre this morning, should go their doctor if they are feeling unwell.

Customer appointments at the centre today will be rescheduled at no extra cost.

For urgent transactions, VicRoads urges customers to call 13 11 71 or visit their nearest centre at either Colac or Hoppers Crossing.

Transactions can also be completed online at www.vicroads.com.au.

The health and safety of VicRoads staff and customers is our first priority. VicRoads apologises for any inconvenience caused.