How investigators figure out the cause of a fire

Minneapolis fire investigators say it will take weeks for them to determine the cause of the blaze that killed six people on the city's south side last week.

Friday's fire in a building that housed an Irish pub and half a dozen upper floor apartments was the deadliest in Minneapolis in almost 25 years.

Officials have said the fire probably started in a corner apartment on the building's second floor.

To find out just how investigators go about pinpointing the cause of a fire, we contacted Denise DeMars with the State Fire Marshal's office.