CALGARY -- Calgary fire officials are working to determine the cause of a large blaze that broke out inside a northeast home on Thursday.

Emergency crews were called to an unoccupied house in the 5200 block of 85 Avenue N.E. at about 1:25 p.m. following several calls to 911 dispatch.

While firefighters were headed to the scene, a second alarm was called due to the sheer volume of smoke and fire coming from the home.

Once they arrived, crews immediately began a defensive attack on the fire due to structural and safety concerns. Through those efforts, firefighters managed to contain the blaze to the house of origin, though a number of trees were scorched.

The cause of the fire is undetermined at this time.

If members of the public have any information, photos or video of this fire, especially prior to CFD (Calgary Fire Department) arrival on scene, please email