The PGA Tour, which is staging the Dell Match Play Championship in Austin, Texas, this week, says its security advisers are collaborating closely with law enforcement to try to ensure the safety of players and fans.
The PGA said Monday that it doesn't comment on the specifics of its security measures but that the safety of players and fans is its top priority.
Austin has been the site of four bombings this month, including one Sunday night that was triggered by a tripwire and seriously injured two men. The first three attacks used package bombs left on people's doorsteps. They killed two people and injured two others.
Authorities believe the attacks are the work of a serial bomber.