Newly released 911 records from the June 12 mass shooting at the Pulse nightclub in Orlando provide a harrowing look into what victims saw and heard during the roughly four-hour attack that left 49 dead and 53 injured.

The logs -- known as the "in progress incident report" -- include the notes 911 dispatchers took as they received calls by the minute. Released Tuesday by the City of Orlando in cooperation with the FBI , the reports describe shots fired; eyewitnesses saying that the gunman also had a bomb; and heartbreaking updates of families calling 911 as their loved ones trapped inside the club stopped responding to text messages.