A Harris County grand jury today has cleared a Houston police officer in the fatal shooting of an unarmed man in January.

The panel, which has been meeting for months, cleared officer Juventino Castro in the death of 26-year-old Jordan Baker.

The inquiry marked one of Harris County's first grand jury deliberations in a police shooting following recent unrest over the lack of indictments in the officer-involved deaths of Michael Brown in Ferguson, Mo., and Eric Garner in New York.

Baker's death has gained national attention as another unarmed black man killed by police, a trend that has sparked protests and calls for body cameras on officers.

Janet Baker, who spent most of Tuesday and Thursday last week awaiting a decision at the Harris County Criminal Justice Center, had maintained that Castro profiled her son - who was wearing a black hoodie - as a criminal. Along with activists, she has been accompanied by mothers whose sons have been injured or killed in local shootings.

The grieving mother and her supporters had remained hopeful that the grand jury would indict the officer so that his actions can be considered by a trial jury.

"I want to express my deepest sympathies to Janet Baker and the entire Baker family," said Harris County District Attorney Devon Anderson in a statement. "I know they are disappointed, but the grand jury's decision means they found that there was no probable cause to believe a crime was committed. It does not constitute an endorsement of the officer's actions."

In order for an indictment to occur, at least nine of the 12 grand jurors must find there is probable cause. Anderson said that the panel's decision shows there was not enough evidence for a criminal charge.

Flanked by supporters, Janet Baker slowly walked out of the grand jury waiting room and faced a throng of news cameras.

She said her son was simply at a shopping center three blocks from his home.

"I intend to seek justice for Jordan," she said in a soft, breathless whisper. "We just have a lot of work to do."

When asked if she had something to say to Castro, she responded that she would rather speak to the system that cleared him.

Meanwhile, U.S. Rep. Sheila Jackson Lee, D-Houston, issued a statement that said, in part:

"Houston has an African-American population of 23.7 percent. However, as recently as 2012, African-Americans accounted for 48 percent of victims killed by the police. This cannot and must not continue. This case may be an incident involving racial profiling and the use of excessive force.

"I am therefore calling upon the U.S. Department of Justice to investigate the killing of Jordan Baker and to take appropriate action, including convening a federal grand jury, to ensure that his civil and constitutional rights are vindicated."

Police were amply prepared for a demonstration in Houston, with dozens of officers on standby and metal barricades lined up in front of the courthouse steps.

Yet only about a dozen protesters gathered outside following the grand jury's decision. Many held signs asking for justice as they sang, "We ain't gonna stop till people are free." And, later, "I can't breathe," citing Garner, who was killed by a police officer in New York City earlier this year.

"It's not about one case," Kofi Taharka of the National Black United Front said at the protest. "The whole system is guilty, corrupt."

Activist Deric Muhammad said the decision confirmed Houston as "Ferguson, Texas."

"Jordan Baker was bothering nobody. He didn't have a weapon on him," Muhammad said. "He was racially profiled."

He announced a citywide protest at 3:30 p.m. Monday outside the courthouse at 1201 Franklin.

Houston attorney Sadiyah Evangelista said she will be filing a federal complaint with the Justice Department on behalf of the Baker family.

"Regardless of the grand jury's decision, Jordan Baker's death will not be in vain. We have decided that the push for justice will not stop in the secret halls of the Harris County grand jury. We're taking it further," Muhammad said. "We obviously have a system that don't give a damn about us."

The shooting happened in the 5700 block of West Little York near Antoine, where Baker encountered Castro.

The officer, who was in uniform and had been on the force for 10 years, was working an extra security job at the location because the strip mall's businesses had experienced a recent string of robberies, according to the Houston Police Department.

Castro's attempt to stop Baker in the parking lot led to a brief struggle and foot chase, an HPD news release said. When Baker stopped running away, he reached into his waistband and charged the officer, police contend. Castro fired his gun once and struck Baker. The officer was not injured in the incident, police said.

Castro was placed on standard three-day administrative duty immediately following the shooting. An internal investigation to determine if the officer violated any agency policies or procedures was set to begin after the grand jury delivered its decision, HPD Chief Charles McClelland confirmed last week.

Harris County grand juries have cleared HPD officers of criminal wrongdoing in all shootings since 2008. More than a quarter of the 121 civilians shot by the department's officials from 2008 to 2012 were - like Baker - unarmed, according to a Houston Chronicle analysis.

Reporter Rebecca Elliott contributed to this report.