About 100 people carried signs and flags as they marched to the Immigration and Customs Enforcement Building in downtown Phoenix Sunday night.

The rally, hosted by immigrant-rights group, Promise Arizona, was planned over two months ago. However Reverend Ken Heintzelman said the recent changes to national immigration policy changed the tone and intensity of the event.

In early May, U.S. Attorney General Jeff Sessions announced a “zero tolerance” policy and said that would include separating children from parents at the border to deter immigration.

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The move has sparked heavy criticism, and the protesters chanted “keep families together,” while marching from The Central United Methodist Church down Central Avenue.

“The timing of this is not a response to what Trump is doing but it is very much in line with it,” Heintzelman said.

The Shadow Rock United Church of Christ, where Heintzelman is a senior pastor, has provided refuge to undocumented migrants in the past. He says he disagrees with the policy on religious, moral and practical grounds

“That’s just not gonna work,” he said. “Because people are coming from countries where it’s so much worse that they’ll take their chances at the U.S. Border.”

More than 600 children were separated from their families from May 6 to May 19, according to executive director of Promise Arizona Petra Falcon.