EL PASO, Texas (Border Report) – U.S. officials say they were forced to fire pepper balls at a crowd of migrants who repeatedly tried to force their way into the United States late Monday over a railroad bridge straddling Juarez, Mexico, and El Paso, Texas.

The mass entry attempt took place only hours after the U.S. Border Patrol warned about social media rumors inciting migrants in Juarez to approach the border because immigration officials allegedly would be processing asylum-seekers at a railroad bridge in South El Paso.

The rumors were false, but up to 1,000 migrants walked up to the railroad bridge on Monday.

The pepper balls started flying after some migrants walked onto the U.S. side of the structure, known in Juarez as the Puente Negro (Black Bridge), started shaking the border wall and allegedly threw rocks in the direction of U.S. Customs and Border Protection officers on the American side.

At 8:50 p.m., the group approached and threw rocks at the locked gate in an apparent attempt to breach the crossing and make a mass entry, federal officials told Border Report. CBP officers deployed their pepper ball firing system on various occasions until the crowd dispersed back to Mexico. A Border Report video of the incident shows most of the pepper balls striking the fence and a metallic sign on the fence.

“CBP is working to maintain the legal and orderly flow of entry to the U.S. while protecting the safety and security of legitimate trade and travel,” CBP said in a statement. “No one should believe the lies of smugglers. Individuals and families without a legal basis to remain in the United States will be removed.”

But immigrant advocates in El Paso who went to Juarez on a fact-finding tour on Tuesday said U.S. federal officials used “disproportionate” force against asylum-seekers. They said CBP and any other agencies involved in crowd-control efforts failed to de-escalate the situation, and will be asking the Department of Justice to review the incident.

“They tried to be processed because they heard they would be processed, and then they were tear-gassed. We’re talking about families, children,” said Fernando Garcia, executive director of the El Paso-based Border Network for Human Rights.

Garcia on Monday met with about 100 migrants outside Juarez’s Migrant Assistance Center who shared stories of how they were filled with hope at the possibility of being allowed to cross into the U.S. – which quickly turned to confusion and then panic when shots rang out and the pepper gas reached them.

“This is not the way migrants or asylum-seekers should be treated,” Garcia said. “It is important to bring reliable information to these families so they can make informed decisions. […] I believe there is a system to de-escalate situations to regain operational control, but their response was shooting tear gas. I don’t believe that was the right procedure.”

Border Report interviewed several migrants who witnessed the incident on Monday night.

Nicaraguan migrant Oliver Castillo said he saw a small group of young people throw rocks toward the border fence.

“They are going to close the door to all of us because of what a few people did,” Castillo said. “It is not easy being (in Mexico), people get desperate. There is no justification for them to shoot at us, but it is understandable they felt they needed to do something.”

Castillo, who has been in Juarez for only five days, said migrants not only must endure shortcomings and even violence on the way to the U.S. border, but also have to be careful in how they approach authorities in Mexico and the U.S.

“I just want to be reunited with my daughter on the other side. She is an asylum-seeker. I want to join her, work and do the best I can so I can stay in the United States,” he said.

But Alexa, who is in Juarez with her son and daughter waiting for an asylum appointment in the U.S., said innocent bystanders got hurt in Monday night’s melee.

“We were asleep when they released the tear gas. Then the (Mexican) cops started to assault us. My 14-year-old girl went into convulsions because of the cops’ aggression, because of the way they came in, beating people up,” she said.

Milagros, another Venezuelan mom, said the smell of the pepper gas woke her up as she slept on the street. She quickly gathered her daughters Rachel and Richelle and bolted away from a sidewalk near the Paso del Norte International Bridge.

“I felt the itch from the gas and left to protect the girls,” she said. “There is a lot of disinformation. Some people tell you one thing, then the authorities tell you something else. They say families are welcome, then they are not. You don’t know who to believe.”