Clark County Sheriff Joseph Lombardo on Wednesday evening presented the following timeline for Las Vegas gunman who killed 58 people and himself in the deadliest mass shooting in modern US history.

Stephen Paddock, 64, strafed an outdoor concert on Sunday night from his 32nd-floor suite of the Mandalay Bay hotel on the Las Vegas strip.

Timeline

10.05 pm — First shots fired by the suspect. This was seen on closed-circuit television from the concert venue.

10.12 pm — First two officers arrive on 31st floor and announce gunfire is coming from directly above them.

10.15 pm — Last shots are fired from the suspect per body worn camera.

10.17 pm — First two officers arrive on 32nd floor.

10.18 pm — Security officer tells Las Vegas Metropolitan Police Department officers he was shot and gives them exact location of suspect's room.

10.26-10.30 pm — Eight additional officers arrive on 32nd floor and begin to move systematically down the hallway, clearing every room and looking for any injured people. They move this way because they no longer hear the gunfire of an active shooter situation.

10.55 pm — Eight officers arrive in stairwell at the opposite end of the hallway nearest to the suspect's room.

11.20 pm — The first breach was set off and officers entered the room. They observed the suspect down on the ground and also saw a second door that could not be accessed from their position.

11.27 pm — The second breach was set off, allowing officers to access the second room. Officers quickly realised there was no one else in the rooms and announced over the radio that the suspect was down.