Updated with LAPD Chief Charlie Beck's comments, after the jump. Originally posted at 1:13 p.m. Monday. Read about the L.A. police union's response to the protests here.

Four people were arrested and three officers sustained minor injuries from thrown rocks and bottles after police stood off with an estimated 100 demonstrators Monday night and into Tuesday morning at West Sixth Street and South Union Avenue, the site of a controversial officer-involved shooting on Sunday. Los Angeles police declared a citywide tactical alert, shut down Sixth Street and declared an unlawful assembly, according to police frequencies and Fox 11 News. Some demonstrators were arrested by late Monday after rocks and debris were thrown at officers and trashcans were set afire.

People angered over a Los Angeles police shooting that took the life of a knife-wielding man over the weekend gathered at the department's nearby Rampart Division building in Westlake beginning Monday afternoon to protest the lethal force used to subdue the suspect.

Police called for reinforcement about 1 p.m. Monday after as many as 40 people gathered at the Rampart Division at 1401 W. Sixth St. to protest the officer-involved shooting. Another 30 to 40 people were said to be amassing at the nearby scene of the shooting, a bustling neighborhood near Sixth and Union.

The shooting happened shortly after 1 p.m. Sunday when bicycle officers were flagged down to intercept an “irrational” suspect with a knife. Police said he had been threatening a woman with a knife, was intoxicated, was a habitual drunk and was a known problem in the area.

At least one officer opened fire when the man did not respond immediately to orders to drop his deadly weapon, leading to the shooting, said Los Angeles Police Department Officer Gregory Baek. A coroner's official said the dead man was Guatamalan and about 38-years-old. The victim was later identified as 37-year-old Manuel Jamines, a Guatemalan construction who had three children.

A crowd formed after the shooting and witnesses seemed incensed, with some arguing that the man didn't speak English, didn't understand the cops, and should have been given more time to comply. Witnesses indicated the suspect was shot in the head in front of onlookers.

“Assassin, assassin,” one bystander was heard saying on an NBC4 news report. “You will pay for this.”

Police disputed accounts that he didn't understand officers' orders: They said the suspect was ordered to drop his weapon in both English and Spanish.

The suspect “was ordered several times in English and Spanish to drop the knife, and failed to comply,'' LAPD Chief Charlie Beck told the Police Commission Tuesday afternoon. “The suspect then raised the knife over his head and advanced on officers, at which time an officer-involved shooting occurred. The suspect fell to the ground where he was taken into custody without further incident and a knife was recovered at the scene.''

“The investigation revealed that several citizens were threatened by the suspect with a knife just prior to the officers' arrival,'' Beck said.

A police spokesman said tensions were high in the immigrant-dominated community west of downtown because the department had been cracking down on illegal street vendors, a staple of the neighborhood.

Beck's comments echoed facts put forward by others in the department.

“We have located several witnesses who told our investigators that they saw the suspect threatening people with the knife before our officers arrived,'' said LAPD Lt. Andrew Neiman. “One of those was a woman who said she saw the suspect threatening a

woman with a knife. Her attention was drawn by a crying 4-year-old who was standing next to the woman.''

“Instead, he came after the officers with a knife raised in the air leading one of the officers to fire at the suspect fatally wounding him,'' said Neiman.

Following the shooting a crowd reportedly encircled the man's body, with one police supervisor at the scene quickly becoming the source of threats and name-calling.

Police late Monday stated that a community meeting to address concerns about the shooting was going to be held soon. Meanwhile a heavy police presence was planned for the area Tuesday.

Anyone who witnessed the confrontation was asked to call the LAPD's Force Investigation unit at 213-486-5200.

-With reporting from City News Service. Got news? Email us. Follow us on Twitter, too: @dennisjromero.

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