The Justice Department said Sunday that it will review the George Zimmerman case for possible civil rights violations, after a jury acquitted the Florida neighborhood watch volunteer in the fatal shooting of 17-year-old Trayvon Martin.

As Zimmerman's attorney cautioned that his client's safety is at risk, the Justice Department responded to appeals from NAACP President Benjamin Todd Jealous and several lawmakers to keep investigating the defendant.

The department may find itself in a vulnerable spot. Last week, a conservative watchdog accused an obscure agency within the DOJ of helping support the "pressure campaign" against Zimmerman in the wake of the shooting last year. Judicial Watch claimed documents and public accounts showed "extraordinary intervention" by the department in the campaign that eventually led to Zimmerman's prosecution.

The department, however, claims that it dispatched agency representatives to reduce tensions in the community – not to take sides.

President Obama himself caused a stir last year by remarking in the days after the shooting that if he had a son, he would “look like Trayvon.” On Sunday, however, Obama urged calm and declared, “the jury has spoken.”

The Justice Department, in announcing it would examine possible civil rights violations, said it has already been reviewing the handling of the criminal case in which Zimmerman, a Hispanic, fatally shot Martin, a black teen, in February 2012, raising concerns about such issues as racial profiling.

"The Department of Justice's Criminal Section of the Civil Rights Division, the United States Attorney's Office for the Middle District of Florida, and the Federal Bureau of Investigation continue to evaluate the evidence generated during the federal investigation, as well as the evidence and testimony from the state trial," the Justice Department said in a statement Sunday. "Experienced federal prosecutors will [now] determine whether the evidence reveals a prosecutable violation of any of the limited federal criminal civil rights statutes within our jurisdiction, and whether federal prosecution is appropriate in accordance with the Department's policy governing successive federal prosecution following a state trial."

Jealous started the drive to pressure the DOJ to continue its probe by posting a petition Sunday morning on the website MoveOn.org that was addressed to Attorney General Eric Holder.

"The most fundamental of civil rights -- the right to life -- was violated the night George Zimmerman stalked and then took the life of Trayvon Martin," Jealous wrote in the petition.

An all-female six-member jury announced late Saturday that it found Zimmerman ‘not guilty’ of all counts against him, which included charges of second-degree murder and manslaughter.

Jealous told CNN’s “State of the Union on Sunday morning, “There is reason to be concerned that race was a factor in why (Zimmerman) targeted young Trayvon.”

He also said he has not spoken directly with Holder but has spoken to his senior people.

“We are glad that what they began months back continues, which is a serious reviewing of everything that came out in this case, everything that was known before this case,” Jealous said.

Earlier in the day, Senate Majority Leader Harry Reid urged the Justice Department to review federal charges against Zimmerman.

“I think the Justice Department is going to take a look at this,” he said on NBC’s “Meet the Press.” “This isn’t over with and I think that’s good.”

The Rev. Al Sharpton on the same show condemned the “stand your ground” law under which Zimmerman won acquittal, adding of his plans, "I will convene an emergency call with preachers tonight to discuss next steps and I intend to head to Florida in the next few days."

Meanwhile, Mark O'Mara, who defended Zimmerman at trial, suggested his client’s safety was at risk. "There still is a fringe element that wants revenge," O'Mara said. "They won't listen to a verdict of not guilty."

In August 2012, O'Mara said Zimmerman and his wife, Shellie, had been living like hermits and weren't working because they feared for their safety.

After Saturday's verdict, police, officials and civil rights leaders urged peace and told protesters not to resort to violence.

Demonstrators across America rallied against Zimmerman on Sunday. Most of the protests were peaceful, but in cities like Oakland, Calif., there were reports of vandalism.

"I now ask every American to respect the call for calm reflection from two parents who lost their young son," Obama said in a statement Sunday.

The Associated Press contributed to this report.