Protestors took to the streets of South Los Angeles Monday, July 15, 2013, venting their anger in the verdict of the George Zimmerman case. Zimmerman was found not guilty in the death of teenager Trayvon Martin. Police said protestors damaged cars and businesses along Crenshaw Boulevard and made 13 arrests. (23927)

SOUTH LOS ANGELES, Calif. — One day after a mob broke away from a Trayvon Martin prayer vigil and went on a violent rampage along Crenshaw Boulevard, Los Angeles police Chief Charlie Beck today repeated his vow that the department will take a much tougher stance during future protests to prevent more trouble.

“We cannot allow a small group of individuals to not only damage … and strike fear the community, but also to destroy the message of so many in the community,” Beck said during a Police Commission meeting.

On Monday night, a 150-strong mob split from a Leimert Park prayer vigil and rally and went on a rampage along Crenshaw Boulevard, damaging several businesses, assaulting people, vandalizing cars and blocking traffic, police said. Fourteen people were arrested.

Beck told the Police Commission the department would not tolerate any more violent demonstrations and called on the public to “stay within the parameters of the law” if they intend to march again. He also said the department would increase the number of officers in the Leimert Park area tonight. As many as 350 officers were deployed in the area Monday night.

Police give “a lot of leeway” to demonstrators, even if they do not have a permit, to allow them freedom of speech, Beck said, but “unfortunately we won’t be able to do that tonight because of the circumstances of last night.”

Of Monday night’s protesters, Beck said, “Peaceful demonstration was not what they weren’t interested in.”

Monday was the third consecutive day the LAPD went on a tactical alert in response to protesters upset over the acquittal of Florida block watch captain George Zimmerman in the killing of 17-year-old Trayvon Martin. The alert allows stations to keep officers on duty past the end of their shifts.

Beck noted that his officers also responded to six homicides over the weekend — and the department could have used the help of the more than 300 officers who were instead assigned to the demonstrations.

“We had an extremely violent weekend during which I would have loved to have used those same resources to prevent further violence but I was unable to do so,” he said. “This is a relatively small police department with a huge mission, and it taxes us to the extreme when we have to deal with situations like this.”

Of the 14 people arrested Monday, seven adults and six juveniles were suspected of failing to disperse and one was suspected of inciting a riot, according to LAPD Detective Gus Villanueva.

Firefighters put out several small fires and responded to “a couple” of minor injuries, according to Erik Scott of the Los Angeles Fire Department, which had 30 extra firefighters deployed to the area in case of trouble, along with arson investigators and chiefs who were working with the LAPD.

At a late-night news conference, Mayor Eric Garcetti lashed out at protesters who engaged in violent acts.

“The trial that we saw in Florida has ignited passions, but we have to make sure that it will not ignite this city and we see a small group that has taken this opportunity to exploit this situation — acts of vandalism, attacks against other community members,” Garcetti said.

“The Martin family was very clear that those who sympathize with their plight, the best way to honor their son and their loved one is in a nonviolent manner. People deserve to be able to express their opinions and we will continue to allow that … to happen, but people also deserve to be safe on their streets and in their cars.”

Beck said last night his department wants to facilitate the exercise of First Amendment rights by residents who want to protest peacefully, but the violence has forced LAPD to take a firmer stance in terms maintaining law and order.

“Unfortunately, we were sorely disappointed by the actions of about 150 individuals who decided to break away from the peaceful protest and vandalize and assault individuals upon Crenshaw Boulevard,” he said.

“We deployed over 300 police officers. A dozen arrests, multiple incidents of vandalism, several incidences of assault — this will not be allowed to continue. Unfortunately, the rights of the many have been abused by the actions of a few.

“Because of that, tomorrow (Tuesday) the LAPD will have a much stricter posture in the way that we deal with people taking the streets of Crenshaw Boulevard.”

Beck also warned parents to not send their children to protests in the area.

The breakaway group headed north on Crenshaw Boulevard around 5:30 p.m., then went south as police set up skirmish lines along several streets, said Lt. Andy Neiman, an LAPD spokesman.

Protesters did some damage to the Wal-Mart at Baldwin Hills Crenshaw Plaza, and a window was smashed at a Jack in the Box restaurant.

At a news conference this morning near the damaged Wal-Mart, community activist Earl Ofari Hutchinson announced that “community peace monitors” will be deployed in various areas tonight to guard against a repetition of the violence.

“In the memory of Trayvon Martin, his mother, his father, they have asked for this repeatedly — over and over again — don’t use violence, don’t use destruction, don’t use his name, don’t use his memory for violence,” Hutchinson said.

During Monday night’s disturbance, KCAL9 reporter Dave Bryan and a cameraman were tackled by what appeared to be a pair of protesters while conducting an interview. According to the station, both were treated for minor injuries. Meanwhile, a KPCC public radio reporter told another photographer she had her phone and a video card taken from her by suspects who tried to take her camera.