WASHINGTON (CNN) -- The Department of Homeland Security and FBI have issued security bulletins to raise awareness regarding "terrorist interest" in attacking sports and entertainment venues as well as luxury hotels.
The bulletins, which were sent to law enforcement Monday, said that authorities did not know of any credible or specific terrorist plots to attack U.S. stadiums, arenas or luxury hotels.
However, it said that terrorist groups such as al Qaeda view crowded stadiums and arenas as potential targets. It said hotels are also attractive targets for terrorists.
The Department of Homeland Security said it released the notes to assist law enforcement partners as they go about their daily duties.
"While DHS and FBI have no information regarding the timing, location or target of any planned attack, we believe it is prudent to raise the security awareness of our local law enforcement partners regarding the targets and tactics of previous terrorist activity," the department said.
The bulletins did not mention the recent arrest of three men in connection with what the Justice Department has said was a plot to detonate bombs in the United States. The men are charged with lying to federal agents during the probe of the alleged plot.
The bulletin on stadiums and arenas said that previous attacks against crowd gatherings have included improvised explosive devices and car bombs, "tactics that are also applicable to many stadiums and arenas. ...
"Detained terrorists have also discussed the use of aircraft and chemical weapons to attack stadiums and arenas. "
It said the al Qaeda training manual lists " 'blasting and destroying the places of amusement, immorality and sin ... and attacking vital economic centers' as a key objective."
The bulletins on luxury hotels said analysis of previous attacks abroad and thwarted plots showed that terrorists have used paramilitary and "small unit" tactics, explosives, improvised explosive devices and car bombs.
It said hotel owners can protect their properties by installing fencing or walls around the buildings and populated areas; implementing random screening of people and their possessions; and training security staff.