LAS VEGAS -- Las Vegas police on Wednesday released some body-camera video from officers responding to the deadliest mass shooting in modern U.S. history. Inside the room officers found assault-style weapons scattered around.

A video obtained early by the Las Vegas Review-Journal, and have since been sent to CBS News, shows officers responding to gunfire. One video shows an officer passing people still playing slot machines and telling an employee that "there's a shooter. He's shot and killed multiple people already." One video displays officers ordering people to leave the casino and telling an employee, "We need to evacuate the whole casino. Get everyone out of here."

Other video footage shows officers checking rooms in the Mandalay Bay before breaching a door and entering the 32nd-floor hotel suite where Stephen Paddock unleashed gunfire on a country music festival last October.

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In one clip, a Las Vegas officer is heard saying "Breach! Breach! Breach!" before a loud bang and a fire alarm begins to sound. An officer grabbed an assault-style rifle from the ledge of a broken window and other weapons were found inside the room.

Officers can be heard shouting to each other to say they have checked parts of the room.

Additional video footage shows officers inside a room reading an address off Paddock's driver's license, while another video shows officers in a stairwell walking down a hallway behind armored shields and encountering a security guard holding a handgun.

Officers are heard talking about finding "multiple cameras" on a room service cart in the hallway outside the suite, which Paddock apparently placed to monitor anyone approaching as he carried out the attack. Officers were also heard discussing if there were any indications of two shooters.

Footage also shows Paddock's body on his back, clad in dark pants and a long-sleeve shirt with a glove on his left hand. An apparent pool of blood stains the carpet near his head as a police SWAT officer walks past.

Police and the FBI have said Paddock killed 58 people and injured hundreds more before killing himself as authorities closed in.

The footage doesn't show what the first officer through the door saw because he didn't activate his body-worn camera. That disclosure by police lawyers late Tuesday raises questions about whether officers followed department policy.

The newly released videos represent a sample of hundreds of hours of bodycam recordings that don't answer the question of why Paddock opened fire, Clark County Sheriff Joe Lombardo told reporters Tuesday.

Police and the FBI have said they believe Paddock, a 64-year-old former accountant and high-stakes video poker player, acted alone.

The police investigation is not finished, said Lombardo, who oversees the department and called the preparation and release of documents sought by the media a "monumental task" that would divert resources from police work.

"What is seen on those videos in no way changes the facts that we were able to clarify for you shortly after the crime," he said.

Lombardo referred to a preliminary police report released Jan. 19 that said Paddock meticulously planned the attack, researched police SWAT tactics, rented hotel rooms overlooking outdoor concerts and investigated potential targets in at least four U.S. cities.

The sheriff's top spokeswoman, Carla Alston, said Wednesday that no one in the agency would comment about whether the first officer through the door followed proper procedure by not activating his camera or whether he had been disciplined for violating policies.

The Police Department requires officers to activate body cameras during calls that lead to interaction with residents and searches.

The Associated Press and other media outlets sued to obtain videos, 911 recordings, evidence logs and interview reports.

The department had sought to delay the release of the videos and recordings, but the Nevada Supreme Court last month denied their motion. Lombardo said the department would release more records in batches in coming weeks in accordance with the court order.

In a statement, Lombardo said he believes the release of the materials will have a "significant impact" on the victims.

"We believe the release of graphic footage will further traumatize a wounded community and for that we apologize," he said.