Authorities are getting ready to release details on the suspected cause of a fire that killed seven people, including three children, in a Lowell apartment building last week.

Middlesex District Attorney Marian Ryan, State Fire Marshal Stephen Coan, Lowell Fire Chief Edward Pitta and other officials planned a news conference late Tuesday afternoon at a fire station located just 100 yards from the scene of the fire.

A fire ripped through the building before dawn Thursday, trapping some residents and prompting dramatic rescues by firefighters as others climbed out or were dropped from windows.

The fire killed Torn Sak, his longtime girlfriend, Ellen Vuong, and three of their five children. Family members and friends identified the other victims as 38-year-old Tina Christakos and 72-year-old Robert Downs.