A four-alarm fire tore through a building housing two landmark restaurants in Yorkville is being treated as suspicious, Toronto Fire Services said.

Both Sotto Sotto and Spuntini Ristorante & Bar went up in flames as a blaze tore through the buildings at 116 and 114 Avenue Rd., south of Davenport Road Thursday night.

The fire is being treated as suspicious because of the extent of the damage and the fact the building had been unoccupied for several days, Toronto Fire Services said Friday afternoon.

The fire is believed to have started at 116 Avenue Rd. around 7:30 p.m. and then spread through the roof to 114 Avenue Rd., Toronto Fire Services said.

No one is believed to have been in the building at the time of the fire. The restaurants were both closed for Christmas and a tenant who lives in the apartment above was away visiting family.

Damage has been estimated at more than $1 million.

Flames were still visible on the roof Friday morning and firefighters are expected to remain on scene well into the day.

“The roof has collapsed,” Platoon Chief Kevin Shaw told reporters Friday morning. “Firefighters are dealing with that now. You’ve got hot areas that are still smoldering underneath the roof. It’s making it difficult for us to knock the fire completely down.”

Shaw said firefighters had trouble battling the blaze Thursday night due to the intense heat.

One firefighter sustained minor burns while battling the flames, Toronto Fire Services said.

Shaw said police are also looking into the fire and will be reviewing surveillance footage to try and determine what happened.

The Ontario Fire Marshal’s Office is now on scene investigating. The cause of the fire remains unknown.

A stretch of southbound Avenue Road is expected to remain closed through Saturday morning and possibly longer, Shaw said.

Restaurants frequented by stars, VIPs

Both restaurants were known as hang outs for celebrities and powerful politicians.

Prime Minister Stephen Harper and his wife Laureen dined at Sotto Sotto with several friends following the funeral for former finance minister Jim Flaherty in April.

The restaurant was also familiar to Hollywood stars like Brad Pitt, Johnny Depp and others, who are often spotted in the area during the Toronto International Film Festival.

“Damn. My second home. Gone but not forgotten. #SottoSotto,” Toronto rapper Drake posted along with a picture of the restaurant on Instagram.

Mayor John Tory tweeted Friday that he is “saddened” by the destruction of the two iconic restaurants and thanked firefighters for their efforts to control the fire.

Area residents also expressed disbelief at the loss of the local landmarks.

“It’s just awful. It’s overwhelming actually,” one woman told CP24 Thursday night.

“I’ve never seen a fire like this before,” another area resident said. “It’s kind of a rude awakening on Christmas Day.”

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