BALTIMORE (AP) — Prominent Black Lives Matter activist DeRay Mckesson was jailed Saturday night after police arrested him in Baton Rouge while protesting the shooting death of a Black man by police outside a convenience store.

Police officer arrest a man for blocking Airline Highway, a major road that passes in front of the Baton Rouge Police Department Headquarters, during a protest in support of justice for Alton Sterling who was killed Tuesday in Baton Rouge, La. Saturday, July 9, 2016. (AP Photo/Max Becherer) Police arrest activist DeRay McKesson during a protest along Airline Highway, a major road that passes in front of the Baton Rouge Police Department headquarters Saturday, July 9, 2016, in Baton Rouge, La. Protesters angry over the fatal shooting of Alton Sterling by two white Baton Rouge police officers rallied Saturday at the convenience store where he was shot, in front of the city's police department and at the state Capitol for another day of demonstrations. (AP Photo/Max Becherer)

Police officer arrest a man for blocking Airline Highway, a major road that passes in front of the Baton Rouge Police Department Headquarters, during a protest in support of justice for Alton Sterling who was killed Tuesday in Baton Rouge, La. Saturday, July 9, 2016. (AP Photo/Max Becherer) Police arrest activist DeRay McKesson during a protest along Airline Highway, a major road that passes in front of the Baton Rouge Police Department headquarters Saturday, July 9, 2016, in Baton Rouge, La. Protesters angry over the fatal shooting of Alton Sterling by two white Baton Rouge police officers rallied Saturday at the convenience store where he was shot, in front of the city’s police department and at the state Capitol for another day of demonstrations. (AP Photo/Max Becherer)

McKesson, 31, traveled to Louisiana from Baltimore, where he grew up and returned last year after the death of a young Black man being transported in a police van sparked outrage and riots. He waged an unsuccessful campaign for mayor this spring.

He now works for the Baltimore public schools as interim chief of human capital, responsible for staffing schools and dealing with reform. Baltimore schools CEO Sonja Santelises says she’s waiting for more information about the arrest of Mckesson. Santelises told The Baltimore Sun (http://bsun.md/29wJNOR ) she was still waiting to hear exactly what happened.

“This is part of who he is, it’s part of what drives him, and it’s part of what drives him to move the work for kids,” she was quoted as saying.

ARREST IN BATON ROUGE

Brittany Packett, an activist who was with Mckesson on Saturday night, said Mckesson was arrested during the protest on behalf of Alton Sterling, a 37-year-old black man who was shot and killed outside of a convenience store by two White police officers. Video of the shooting, which took place in Baton Rouge on Tuesday, was posted online and set off angry protests.

Packett told The Associated Press that Mckesson was taken into custody after a police officer approached him and said, “you with the loud shoes — if you step back into the street you’ll be arrested.” Mckesson was then tackled by several officers and arrested. She insisted that he was not in the street and that police “intentionally provoked” the protesters.

Booking documents provided by the East Baton Rouge Sheriff’s Office say Mckesson was arrested on a charge of obstructing a highway. An affidavit of probable cause filed by police says Mckesson “intentionally” placed himself in the road after protesters were repeatedly warned via police loud speaker to remain on private property or the curb.

“During the protest, the defendant entered the roadway and was provided another verbal order to exit the lanes of travel. Moments later, the defendant entered the roadway again and was taken into custody by officers on scene without incident,” the affidavit said.

Black Lives Matter activist DeRay McKesson talks to the media after his release from the Baton Rouge jail in Baton Rouge, La. on Sunday, July 10, 2016. McKesson, three journalists and more than 120 other people have been taken into custody in Louisiana over the past two days, authorities said Sunday, after protests over the fatal shooting of an African-American man by two white police officers in Baton Rouge. (AP Photo/Max Becherer)

Black Lives Matter activist DeRay McKesson talks to the media after his release from the Baton Rouge jail in Baton Rouge, La. on Sunday, July 10, 2016. McKesson, three journalists and more than 120 other people have been taken into custody in Louisiana over the past two days, authorities said Sunday, after protests over the fatal shooting of an African-American man by two white police officers in Baton Rouge. (AP Photo/Max Becherer)

EDUCATOR TO ACTIVIST

Mckesson is one of the most recognizable faces to emerge from the Black Lives Matter movement — a former educator who built a national following after leaving his then-home and job in Minneapolis in August 2014 for Ferguson, Missouri, to document the rising anger over race relations after an unarmed Black man, Michael Brown, was fatally shot by a White police officer.

Mckesson was born to drug-addicted parents in Baltimore. His father got clean and moved him to Catonsville, a predominantly White suburb. After high school, Mckesson attended Bowdoin College in Maine.

Mckesson then taught sixth grade in Brooklyn through Teach for America, which places college graduates in poor districts for two-year commitments. He later returned to Baltimore and launched an after-school program before joining the public school system in an administrative job.

He left again in 2013, this time for the Minneapolis school system. When Brown was shot, Mckesson drove 500 miles (800 kilometers) to Ferguson.

Being on the streets, he said, “woke me up.” And so Mckesson returned to Baltimore, with the promise of a spare room at a family friend’s home and a plan to run for mayor.

Black Lives Matter activist DeRay McKesson walks out of the Baton Rouge jail in Baton Rouge, La. on Sunday, July 10, 2016. The prominent Black Lives Matter activist, three journalists and more than 120 other people have been taken into custody in Louisiana over the past two days, authorities said Sunday, after protests over the fatal shooting of an African-American man by two white police officers in Baton Rouge. (AP Photo/Max Becherer)

Black Lives Matter activist DeRay McKesson walks out of the Baton Rouge jail in Baton Rouge, La. on Sunday, July 10, 2016. The prominent Black Lives Matter activist, three journalists and more than 120 other people have been taken into custody in Louisiana over the past two days, authorities said Sunday, after protests over the fatal shooting of an African-American man by two white police officers in Baton Rouge. (AP Photo/Max Becherer)

DIVE INTO POLITICS

He declared his candidacy for mayor in February, one of 13 Democrats in the race. On his political agenda: plans to establish a system of community first-responders to de-escalate violence, and hire people who’ve been affected by police brutality to train officers on racism and community engagement.

“People want hope. They want transparency … a mayor who has a plan, who understands the issues deeply,” Mckesson said in an interview.

On the ground, however, his efforts met with resistance and skepticism, especially from some of Baltimore’s longtime activists. They criticized him for not engaging with them, and questioned whether his campaign is merely a ploy to grow his “brand.”

“Who sent you and who will you serve?” Jamye Wooten, founder and publisher of an online forum linking social justice issues and faith communities, asked in a blog post. “Here you earn your stripes by serving and being in the community when there are no cameras.”

Mckesson placed a distance sixth in the Democratic primary in April.

THE FUTURE

His activism has thrust him to the forefront of the Black Lives Matters movement and his social media presence is huge, with his twitter handle @DeRay counting more than 450,000 followers.

He was one of the Black Lives Matter activists and civil rights leaders who met with President Obama at the White House.

___

AP reporter Rebecca Santana contributed from Baton Rouge.