An overnight fire has badly damaged one of the city's most most-renowned restaurants.

Firefighters responded to the fire at the Allium Restaurant on Holland Ave around 2:38 a.m. Neighbours reported hearing "a big bang and seeing flames visible at the rear of the establishment."

Ottawa Fire says all crews were pulled out of the building at one point, and ordered to use “defensive operations” to battle the fire.

The Ottawa Police Arson unit responded to the scene, calling the fire suspicious, but not saying what led them to that conclusion.

"It was a bad fire," said Constable Martin Cardinal.

"Suspicious is a good title to put on this one."

Cardinal says the damage done to the building is extreme.

"We can see quite a bit of damage from the street level," said Cardinal.

"But once inside the damage is very, very significant."

Business owners in the area say call the fire devastating for the entire community.

"Smelling this morning, I knew something big was happening," said Katrin Kosk, owner of Blumen Studio.

"You right away think, what if, what would you do."

Kosk says it will be a big loss for Wellington West.

"Holland already has a hard time because it's off the main track and Allium has always been a destination and brought people here for everyone," said Kosk.

"It's devastating."

Kosk is among many who say they will rally around their neighbour. 

Allium's owner Arup Jana was out of town when he got the news, telling CTV he is lost for words, but comforted by the overwhelming amount of support from friends, family, customers and all of the Ottawa restaurant community.

There are no injuries. A statement from Ottawa Fire said one woman and one child will be displaced. The Red Cross and Salvation Army are assisting the displaced and anyone impacted by the fire.

- With files from CTV's Christina Succi.