He wasn’t supposed to have a camera.

But in 1967, when the Rev. Martin Luther King Jr. and his chief strategist, the Rev. Wyatt Tee Walker, were arrested during a civil rights protest in Birmingham, Ala., Walker smuggled a tiny camera into the jail.

Inside their cell, Walker unwrapped the camera, which had been taped to Walker’s leg.

As King peered between the jail’s steel bars, Walker raised the camera and snapped.

The photo would become an iconic shot of King.

“A lot of people don’t know, but I took that photo,” Walker told The Washington Post in a 2016 interview in Chester, Va., where a copy hung on a wall in his home.

The pastor, who also played a key role in getting King’s 1963 “Letter From Birmingham Jail” published, died Jan. 23 at his home in Chester, Va. He was 89.

Walker’s smuggled camera was used for a second photo. In that jail cell, which the two civil rights leaders shared for five days more than a half century ago, King snapped a photo of Walker looking out the same steel bars.

It was a rare moment in which King was behind a camera. And it was a rare moment for Walker, one of the masterminds behind some of the most significant civil rights campaigns in U.S. history, to be in front of the camera.

Walker, who tried to remain anonymous as he moved through the South, often traveled to cities targeted by civil rights groups long before a protest would take place. Walker would meticulously devise strategy.

“In Birmingham, I measured how long it would take a young person to go downtown; an elderly person to go downtown,” Walker said. “I counted bar stools. I identified the eating places, the mall and the facilities that could be secondary and tertiary targets for our campaign.”

At the beginning of the Birmingham campaign in 1963, city officials had heard about Walker. But they did not know who he was or what he looked like.

“They knew King’s man was in town,” Walker said, “but they didn’t know who I was.”

Walker, a Freedom Rider who was arrested more than 17 times for challenging segregation in the South, had become executive director of the Southern Christian Leadership Conference in 1961 after King called to recruit him.

“And I told him,” Walker remembered, “whatever he wanted me to do, I would do it.”

Together, they risked their lives again and again in their crusade for equal rights. And six months after Walker snapped the photo of MLK in their Birmingham jail cell, King was assassinated in Memphis.

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