Shortly after President Barack Obama announced Bin Laden's death in a military operation in Pakistan, the State Department said there was an "enhanced potential for anti-American violence given recent counterterrorism activity in Pakistan." A worldwide travel alert was issued for Americans traveling abroad.
U.S. embassies around the world were also placed on alert and warned of the heightened possibility for anti-American violence.
The alert said U.S. embassy operations would continue "to the extent possible under the constraints of any evolving security situation." It noted that embassies and consulates may temporarily close or suspend public services, depending on conditions.
At Los Angeles International Airport, law enforcement officials were visible both outside and inside the airport.
"Each of us are concerned about what could be a potential backlash," said Los Angeles County Sheriff Lee Baca, adding that his department is on heightened alert
Though many passengers said the increased security presence made them feel safe, others were wondering what would happen in the near future.
"It was like great news, but what are the consequences?" said Lorner Evans of England.
Some travelers said were worried about retaliation from Al Qaeda sympathizers.
"I think that everybody is worried in the back of their mind, well, what will happen next? Is this the end? Or is this just the beginning of another phase?" said Dewayne McMullin of La Canada Flintridge.
Air travelers everywhere were reminded of how Sept. 11 changed their feeling of security every time they step into an airport. Flying has become swamped with increased security checks, luggage and body scanning technology, air marshals on planes and pat downs. Even something as a tube of toothpaste or lipstick can be cause for suspicion.
The Los Angeles Police Department has also increased security at all critical sites. That will include places where there are mass gatherings, such as Staples Center for the Los Angeles Lakers playoff game and Dodger Stadium.
"We will be deploying extra police officers at our large sporting events, which will continue this week and include the Dodgers, Lakers playoff," said LAPD Chief Charlie Beck. "We will make sure that not only do our fans remain safe, but those areas are not targets."
Leaders at a Los Angeles news conference Monday had a common message: If you see something, say something. Staying safe from terrorist attacks is a shared responsibility.
Other Western countries also called for vigilance.
Germany Foreign Minister Guido Westerwelle said a "backlash" from Al Qaeda sympathizers could not be ruled out, while British diplomatic missions were advised to review their security, remain vigilant and avoid demonstrations and large crowds of people.
"The world's most wanted international terrorist is no more, but the death of bin Laden does not represent the demise of Al Qaeda affiliates and those inspired by Al Qaeda, who have and will continue to engage in terrorist attacks around the world," said Ronald Noble, the head of international police agency Interpol.
In the U.S., there are no specific threats in the nation's capitol, but authorities there said officers are on heightened alert. Officials said people can expect a large security presence on Monday.
The State Department warned that travelers should not let their guard down, and should remain vigilant and aware of their surroundings especially when traveling abroad.
"There's other terrorists out there, so you have to still be careful. You have to still go through all the checks," said Diane Haynes of Carlsbad.
Despite the concerns of anti-American retaliation, most say they won't let that stop them from traveling.