Geelong on alert as refinery burns

A major fire at the Geelong refinery in Corio has sent smoke billowing across the region, prompting a sweeping Watch and Act warning for tens of thousands of residents.

Emergency services were called to Refinery Road shortly after 11pm on Wednesday, with up to 17 vehicles deployed as crews worked to bring the blaze under control.

A wind change overnight pushed thick smoke south, with authorities urging people to take immediate shelter indoors.

The alert, issued by the CFA, stretches across a large portion of Greater Geelong, from Corio and Norlane through to Belmont, Grovedale and Armstrong Creek.

Residents south of the refinery were told to shut their doors and windows, turn off heating and cooling systems and avoid exposure to the smoke.

Motorist have been advised to steer clear of the area and to keep the roads clear so emergency services can continue their response.

The smoke plume is expected to affect a wide area, reaching from Corio through central Geelong and as far south as Grovedale, with possible impacts extending toward Moolap and Point Henry.

Health officials warn the smoke could pose risks, particularly for people with heart or lung conditions, children, pregnant women and older residents.

Emergency services remain on scene.

More to come.