A Melbourne family has been left devastated after their newly built pasta factory went up in flames in the city’s north.

Fire crews were on the scene in minutes after being called to the Diseb site in Somerton just after 12.30pm, the Metropolitan Fire Brigade said in a statement.

Video taken from the news chopper shows large plumes of black smoke billowing from the 80 x 30 metre building on Fillo Drive.

All people inside the building were evacuated without injury.

The family who owned the factory embraced as flames tore through the site. (9NEWS) (9news)

Emergency services at the scene on Somerton Drive. (9NEWS) (9NEWS)

All people have been evacuated from the site. (9NEWS) (9NEWS)

The blaze has not yet been controlled, and part of the building's walls have collapsed.

An Advice warning has been upgraded to Watch and Act for residents in Broadmeadows, Campbellfield, Coolaroo, Craigieburn, Dallas, Epping, Greenvale, Lalor, Meadow Heights, Roxburgh Park, Somerton, Thomastown, Wollert.

"Anyone located in suburbs adjoining Somerton should take shelter indoors immediately," the MFB said in a statement just after 2.30pm.

“Close all exterior doors, windows and vents and ensure that heating and cooling systems are turned off."

The family who have owned the pasta business for three generations told 9NEWS they are “shocked” by the incident, but have vowed to re-build the factory.

It remains unclear what sparked the large fire. (9NEWS) (9news)

Large plumes of smoke are issuing from the blaze. (9NEWS) (9news)

Fire crews continue to work to control the blaze. (9NEWS) (9news)

Witness Anne told 9NEWS she first thought the fire was an incoming storm because of the vast amount of smoke.

“It was billowing out... over time, in just got bigger and bigger.”

Fillo Drive will remain closed until further notice, with motorists urged to avoid adjoining roads as well.

The cause of the fire remains unclear.

It is expected that emergency service personnel will remain on scene into the night and tomorrow.