ORLANDO, Fla – Two people were killed and several others were hurt in a mass shooting inside an Orlando nightclub early Sunday morning, according to police.

Orlando police were called to the Glitz Ultra Lounge on Universal Boulevard just before 1 a.m.

Police say three off-duty officers were inside when someone started shooting in the right side of the lower level of the club. No officers were involved in the shooting.

In a news release,Orlando Police Department Public Information Officer Michelle Guido said one person was shot and killed inside the nightclub. Nine people were transported to Orlando Regional Medical Center with gunshot wounds. Of those nine, one died at the hospital; one is in critical condition, the rest were being treated for non-life-threatening injuries. Two people were seen at another hospital; one with a gunshot wound and the other with injuries sustained at the club.

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Orlando firefighters said three of the surviving victims were considered "trauma alerts" when they were transported.

Many of those hurt were innocent bystanders, according to police.

"The club has very good security, with their own guards as well as three off-duty police officers. The club did everything it was supposed to do," said Guido, who said she did not want to address any previous incidents at the club.

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Investigators have not released any information about what led to the gunfire or possible suspects in the case.

Stay with News 6 and ClickOrlando.com for updates on this developing story.

Orlando Police Department press conference is below.