ILVER SPRING, Md. - Federal and local authorities are expected to provide an update into their investigation of an explosion and fire at a Maryland apartment building last week that killed seven people.

Officials from the Montgomery County police and fire departments, along with the Bureau of Alcohol, Tobacco, Firearms and Explosives and the National Transportation Safety Board are scheduled to speak at a news conference Friday at a Silver Spring community centre near the site of the Aug. 10 explosion at the Flower Branch Apartments.

Searchers have recovered seven bodies from the rubble left behind by the explosion, which shook homes more than a mile away.

On Wednesday, the NTSB, which has regulatory authority over gas lines, said it was formally launching an investigation. Some residents reported smelling gas before the blast.