Criminal investigation

Las Vegas gunman fired 1,100 rounds when he shot dead 58 and injured 500 and he had 4,000 MORE rounds left

The Las Vegas gunman who killed dozens of people at a concert last month fired more than 1,100 rounds and had 4,000 more rounds left. 

The newly released estimate from Sheriff Joe Lombardo offers more detail about the deadliest mass shooting in modern US history.

Paddock murdered 58 people and injured hundreds more when he used his Mandalay Bay hotel suite as a vantage point to fire on crowds enjoying the country music show. He then turned one of his weapons on himself.

According to the Las Vegas Review-Journal, the new total includes about 200 rounds fired from Paddock's Mandalay Bay suite and into the hallway of the 32nd floor on October 1, which injured hotel security guard Jesus Campos. 

Lombardo said he was aware of the previously unreported figure because his department's forensics lab is working with the FBI to process all ballistics evidence.

The sheriff also said authorities found about 4,000 unused rounds in the suite. 

Authorities have not determined Paddock's motive or why he stopped shooting.