IIRC he shot the guard as he went in, the guard may have been the first victim.
This is why concealed carry is a must. An armed guard is a designated target.
I haven’t heard much about the armed guard that was at the club, who he was or what happened to him.
Source? I have not heard of any police officers shot that night.
http://www.orlandosentinel.com/news/pulse-orlando-nightclub-shooting/os-orlando-shooting-call-transcripts-20160620-story.html
"According to the FBI timeline, Mateen opened fire at 2:02 a.m., and Officer Adam Gruler, who was moonlighting at the club, exchanged gunfire with him from the parking lot. Gruler then retreated and called for backup... Those backup officers arrived at 2:08 a.m. and went into the club and fired at Mateen, the FBI timeline shows...
It's not clear when that gun battle ended, but Mina said there were no more shots fired by or at the gunman until about 5:15 a.m...."