The shooter, as per FBI, used an AR-style rifle chambered in 5.56mm, a common calibre for such weapons.
In another shooting incident in the US, five people were killed in the town of Wilkinsburg, Pennsylvania. At least two suspects are on the loose, the police said on Thursday.
The Trump campaign has alleged that a significant number of mail-in ballots arrived after the 8 pm deadline of closing of polls on November 3.