2:02 a.m.: An off-duty officer working at the nightclub responds to shots at the entrance and exchanges fire with Omar Mateen. Mateen goes inside.
2:04 a.m.: Additional Orlando Police Department officers arrive on the scene after receiving a call regarding multiple shots fired at the nightclub.
Mateen opens fire and patrons hide, duck and flee.
2:08 a.m.: Police officers enter the building and engage in a gun battle with Mateen, which they say forced him to retreat to the restrooms....