1 killed in Denver commercial structure fire

One person was killed in an early morning fire in Denver's River North district on Tuesday and now arson investigators and fire marshalls are working to determine the cause.

The Denver Fire Department initially said no injuries were reported just after 7 a.m. but around 7:30 a.m., DFD said one person was confirmed to have died in that fire, which is now under control.

The fire broke at least two windows, which is how firefighters entered the building to extinguish the blaze, a DFD spokesman said.

DFD officials did not mention an exact address, but CBS News Colorado's cameras show a sign on the building indicating an address of 3620 Wazee Street.

The area includes several apartment buildings and businesses including Bigsby's Folly Craft Winery and Restaurant, Pesto Italiano and the RiNo Sports Arena.

DFD spokesman Capt. Luis Cedillo said the presence of arson investigators doesn't necessarily mean the fire was human-caused, but those investigators respond to most structure fires.

Cedillo said DFD knows the building was abandoned and the doors were welded shut. Investigators don't yet know the identity of the person who died, how they got into the building, how long or why they were there.

Motorists should expect the area to be shut down for most of the morning as investigators -- about six from Denver police and three more from DFD -- investigate the fire.