World Bulletin/News Desk

U.S. President Barack Obama called on police Thursday to respect demonstrators in Ferguson, Missouri, in an attempt to defuse tensions after four nights of often-violent protests over the police killing of an unarmed black teenager.

"There is never an excuse for violence against police or for those who would use this tragedy as a cover for vandalism or looting," Obama said a televised remarks.

"There's also no excuse for police to use excessive force against peaceful protesters or to throw protesters in jail for lawfully exercising their first amendment rights," he told the press from Edgartown, Massachusetts, near where he is vacationing with his family.

Following the shooting death of 18-year-old Michael Brown in the mostly black St. Louis suburb on Saturday, dozens of protesters have been arrested, and officers in body armor have used SWAT vehicles, riot gear, stun grenades, smoke bombs, tear gas and rubber bullets to break up protests.

Since Sunday, there have been peaceful vigils and demonstrations - with protesters holding their hands in the air and chanting "hands up, don't shoot" - as well as episodes of looting, vandalism and violence.

Missouri lawmakers urged Governor Jay Nixon to step in on Thursday and change the police tactics used in Ferguson, which, they said, were causing an escalation of violence.

"My goal has been to try to move out some of the military responses that they have been embracing and see if we can't get back to good, solid police work that keeps the protesters safe," U.S. Senator Claire McCaskill said during a visit to Ferguson on Thursday.

Nixon told community members at a church near Ferguson that he would make operational shifts so that people would feel a different tone from police on the streets. He did not specify what steps would be taken.

He was due to make an announcement Thursday afternoon.

Ferguson Police Chief Thomas Jackson told reporters the police would work to "facilitate" protests and not escalate tensions, but added that police had to react to crowds that turn violent.

The tactical chief of the police operations at the protests has been the St. Louis County SWAT commander, he said.

Authorities also said Thursday they might rethink their decision to withhold the name of the police officer who was involved in the shooting.

Protesters have said a lack of transparency by police investigating the incident - including the refusal to release the officer's name - had stoked already-high tensions.

They have also called for St. Louis County Prosecuting Attorney Bob McCullough to be removed from the case.

Early on Thursday, a member of the Anonymous hacker activist collective, using the Twitter name @TheAnonMessage, tweeted a name, alleging it was the police officer who shot Brown.

Police and prosecutors strenuously denied that the person named was the officer involved, saying he was not even a member of the St. Louis County Police Department or the Ferguson Police. Later, another collective member, tweeting as @OpFerguson, said the name was incorrect.

Hackers have periodically disrupted the Ferguson police website and other local government sites throughout the week.

THREE INVESTIGATIONS

The shooting and protests have shed a spotlight on race issues in the highly segregated city of St. Louis and its suburbs.

Ferguson has seen a stark demographic shift in recent decades, going from mostly white to mostly black. About two-thirds of the town's 21,000-strong population is black. Still, on a police force of 53, just three officers are black.

Civil rights groups have complained in the past that police in St. Louis County racially profiled blacks, arrested a disproportionate number of blacks and had racist hiring practices.

Amnesty International called on Thursday for a thorough investigation of the shooting of Brown, as well as the tactics used against protesters.

The U.S. Department of Justice, the FBI and the St. Louis County prosecutor's office are all investigating Brown's death.

There is little clarity on what occurred during Saturday's incident.

Police have said that Brown struggled with the officer who shot and killed him. The officer involved in the shooting was injured during the incident and was treated in hospital for swelling on the side of his face, they said.

But some witnesses have said that Brown held up his hands and was surrendering when he was shot multiple times in the head and chest.

Two reporters were among those arrested late Wednesday during protests. Ferguson Mayor James Knowles pledged on Thursday that the reporters would be treated "in a proper fashion."

Obama said "in the United States of America police should not be bullying or arresting journalists who are just trying to do their jobs."

Missouri State Highway Patrol

The Missouri State Highway Patrol will take over security in Ferguson after local police were criticized for militarized tactics during four days of protests, the governor said on Thursday.

Governor Jay Nixon named Highway Patrol Captain Ron Johnson, an African-American who grew up in the Ferguson area, to oversee the security effort.

"What's gone on here over the last few days is not what Missouri is about, it is not what Ferguson is about. This is a place where people work, go to school, raise their families and go to church, a diverse community, a Missouri community," Nixon said at a news conference in Ferguson, where he met with police, prosecutors and members of the community.

"But lately it has looked a little bit more like a war zone, and that is unacceptable."

Nixon said local police would not be pulled out of Ferguson but that state troopers would direct the team.

Additionally, U.S. Attorney General Eric Holder said in a statement that local police had accepted an offer of technical assistance "to help conduct crowd control and maintain public safety without relying on unnecessarily extreme displays of force."

In a brief statement Johnson promised respect for every citizen. There have been dozens of arrests over the last few days and complaints that police have come down too hard on protesters and on reporters covering the demonstrations.