More than 100 protesters took to the streets of central Phoenix late Friday, shutting down traffic to protest planned roundups of undocumented migrants by U.S. Immigration and Customs Enforcement this weekend and treatment of migrant children.

Several people were arrested after nearly two hours of the raucous protest, which brought out a major show of force by Phoenix police.

"Many continue to ignore these consistent requests to clear the light-rail tracks and roadways,'' said Detective Luis Samudio, a Phoenix police spokesman. "Their actions are causing a safety concern to light rail and it is causing a disruption. Officers have deemed this an unlawful assembly and the individuals are subject to arrest."

Samudio said he was unable to confirm how many protesters were arrested, but said "numerous'' people were taken into custody.

The demonstrators spilled onto the street in front of the Phoenix ICE office on Central Avenue north of McDowell Road about 8:30 p.m., after a 90-minute gathering at a nearby church.

More than a dozen protesters began marching on Central Avenue and on light-rail tracks, forcing Phoenix police to block traffic at Central Avenue and McDowell Road to the south, and an intersection north of Palm Lane to the north, while warning the protesters over a loud speaker they could face arrest. Many other protesters lined the side of the street, but more then joined in blocking traffic.

Police gave repeated warnings to people that they could face arrest, but waited as many eventually left the street.

By 10:30 p.m., police moved in and began arresting protesters who refused to move from the tracks and started clearing the street. It was not immediately clear how many arrests were made.

Light-rail trains had been forced to travel on only one side of Central Avenue, escorted by Phoenix police vehicles before eventually being halted a little before 10:30 p.m.

The marchers forced Central Avenue to be blocked off in the area, as they carried signs and shouted slogans calling for justice on behalf of migrants who are seeking asylum.

"Free those kids'' was among the chants protesters shouted as they marched in the street.

Another chant repeated: "Shut down ICE.''

Among the protesters who was refusing to move was Andrea Diaz.

"We have to do what we have to do,'' she said, as she stood in front of a line of Phoenix police officers. "We can't just keep letting them (police) scare us, you know, something's got to give."

Sarah Daigle, a French teacher who recently came from Europe, was among the protesters. She said the U.S. handling of migrant children is big news there.

"It's all over the news in England. It's all over the news in France. It's a shame,'' she said. "If we don't stand here, who's going to do it?''

Brent Whiting, who helped organize the event at Central United Methodist Church where the protesters met before going onto Central Avenue, said the anger over Trump administration policies toward migrants boiled over.

"It came to this because of the inaction of the Trump administration to treat human beings as such,'' he said. "Many of these people are parents of children and they relate to this on an emotional level.''

One protester who left the area told an Arizona Republic reporter that Phoenix police had threatened to use tear gas if the crowd did not disperse, but it did not appear that any gas was used.

An event organizer declined to comment as the demonstration continued in the street after 10 p.m., although the number blocking traffic and light-rail tracks had diminished, as they were watched closely by Phoenix police standing in a line.

By 10:30 p.m., police began arresting those who would not move from the tracks, and by 10:50 p.m., lines of police officers wearing helmets began marching to move the remaining crowds along.

Jessica Bristow was among those who had been sitting on the light-rail tracks earlier.

"I came by myself. I don't know any of these people, but we're all standing for the same thing — for justice, for freedom, for equity for the children and the families who have been separated,'' she said.

The event began as one of hundreds held across the nation called "Lights for Liberty: A Vigil to End Human Concentration Camps."

It was supposed to conclude with a silent vigil, but one protester at the scene said some protesters began using megaphones and moving into the street.

The "Lights for Liberty" organization was started by attorney Elizabeth McLaughlin and is sponsored by the Women's March, the Center for Popular Democracy, the Black Movement Law Project and others, according to its website.

The Phoenix event, along with more then 10 others across Arizona, was organized by a group called AZ Resist, according to one of the group's leaders, Julie Golding. Several hundred people gathered for the central Phoenix rally about 7 p.m. at the Central United Methodist Church, prior to the planned silent vigil.

Several other protests took place in Arizona on Friday. Crowds turned out in Tucson and Flagstaff, as well as in Eloy, near the ICE detention center; and in Show Low, where about 60 people lined the sidewalks.

The protests come amid reports of mistreatment to migrants housed in ICE detention centers. This week, underaged migrants at a Yuma Border Patrol facility reported poor conditions and allegations of misconduct, including sexual assault by some of the agents.

President Donald Trump has vowed to begin rounding up undocumented migrants beginning Sunday in 10 U.S. cities. Phoenix is not included among those cities disclosed by federal officials.

Reach the reporter at chelsea.curtis@arizonarepublic.com or follow her on Twitter @curtis_chels.

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