A federal investigation into a house fire that killed two Connecticut firefighters last summer has determined that fire department officials didn't respond effectively to their mayday calls.

The report Wednesday by the National Institute for Occupational Safety and Health concluded that several factors contributed to the Bridgeport firefighters' deaths.

The report says an incident safety officer and rapid intervention team weren't readily available at the scene, and that ineffective mayday procedures and training also were factors.

Fire Chief Brian Rooney wouldn't comment because the state fire marshal's office is still investigating.

Lt. Steven Velasquez and firefighter Michael Baik died in the July 24 fire.