Monitoring large crowds without controlled access, like the thousands of fans who line the streets for a major event like the Boston Marathon or the crowds that gather outside LSU’s Tiger Stadium before football games, makes it difficult for law enforcement to prevent attacks such as the one Monday in Boston, officials said.

“It’s difficult and that’s why you have to be observant,” Louisiana State Police Spokesman Doug Cain said, noting there is a limit on the number of officers who can be present at an event.

In addition, he said, officers have to strike a careful balance between respecting the rights of attendees and maintaining safety.

“We live in a free society, people can come and go,” he said. “We don’t want nor should we be in the business of shaking everybody down.”

In the aftermath of the Monday bombings at the Boston Marathon, several law enforcement agencies in Louisiana said they were reviewing security policies ahead of upcoming events, such as the New Orleans Jazz and Heritage Festival April 26 to May 5, Bayou Country Superfest in Tiger Stadium May 25-26 and the Color Run in Baton Rouge on Saturday, among others.

Festival Productions of New Orleans, which organizes both Jazz Fest and Bayou Country Superfest, issued a statement Tuesday that said in part “in light of any pertinent information learned regarding yesterday’s events in Boston, we will make any necessary adjustments to our comprehensive security plan.”

Cain said Louisiana is known for large events, such as Mardi Gras, Jazz Fest, LSU football games and countless festivals.

“The good thing is it’s something we do well,” he said. “But you can never become complacent.”

Hours of planning plus cooperation among agencies is key, Cain said.

“Threat assessments, information sharing and partnerships are so important,” he said. “It’s not one magic thing, it’s a matter of good planning, good training, good execution and good after-action.”

At any such event, Cain said, law enforcement will deploy uniformed and plainclothes officers.

“We also have to rely on the public to report things that look out of the ordinary,” he said.

Apart from the crowds, officers go through any gathered intelligence or other information, he said. The effort to secure an area’s safety can include the use of specially trained dogs, aerial surveillance or hazardous material teams, he said.

L’Jean McKneely, a spokesman for the Baton Rouge Police Department, said officers have to be on alert for anything unusual at events that draw large crowds.

“It’s more of a challenge because it isn’t controlled,” he said. “When we see something suspicious that raises our attention, we pay more attention to it.”

McKneely agreed with Cain that public assistance is important.

“We rely on the public a whole lot,” he said.

At a news conference in New Orleans, New Orleans Police Superintendent Ronal Serpas said there were no indications that Jazz Fest might be targeted. Security plans for the event are still being reviewed, he said.

Michael Anderson, special agent in charge of the FBI’s New Orleans Field Office, said his office had received no threats.

“I do want to emphasize that there are no current bomb or shooter threats in the state of Louisiana,” Anderson said.

Organizers of Saturday’s Color Run in Baton Rouge, a 5K road race, said they were reviewing security for the race.

“Due to the recent tragedy, we are revisiting our plans with the local Baton Rouge organizations to see if there are any need adjustments,” spokeswoman Jessica Nixon wrote in an email.

While it may be too early to draw specific lessons from what happened in Boston, officials said it served as a harsh reminder.

“The Boston incident shows us that we can never become complacent,” Cain said. “That’s why we have all these plans and contingency plans.”

Cain said State Police has reached out to Massachusetts law enforcement representatives to offer assistance in the aftermath of Monday’s explosions near the finish line of the Boston Marathon, which killed three and injured scores. Troopers also staffed the Intelligence Fusion Center, a multi-agency, multi-discipline intelligence-sharing headquarters, he said.

“Anytime something like this happens, there is something we can all learn from it,” Cain said. “You certainly want to look at what happened, what steps were taken before the event and after.”

It is still “too early to tell how it happened in Boston, and why it happened,” Cain said.

LSU Police Captain Cory Lalonde said his department would review procedures for football games and events such as Bayou Country Superfest.

“We are looking to that any time incidents of this nature happen,” he said.

In addition to LSU police, Baton Rouge Police, the East Baton Rouge Parish Sheriff’s Office, the Louisiana Department of Public Safety, State Police and some private security firms assist on game days, Lalonde said.

“In the near future, we will be reaching out to all the agencies involved to see if there are changes that we need to make,” he said.

McKneely, the Police Department’s spokesman, said Baton Rouge Provisional Police Chief Carl Dabadie sent an email to officers Tuesday reminding them to stay on alert.

“Things like that can happen anywhere in this country,” McKneely said Dabadie told his officers.

BRPD normally puts its mobile command post at Bayou Country Superfest, McKneely said.

“Ever since 9/11, there has been a heightened awareness of terrorist activities,” he said.

Similarly, East Baton Rouge Parish Sheriff’s spokeswoman Casey Rayborn Hicks said in an email that the Sheriff’s Office would exercise the same caution it does with every event.

“We always do a thorough review when planning security for any new event, and will continue to do such thorough reviews,” Rayborn Hicks said.

Advocate staff writer Allen Powell II contributed to this report.