A woman who is seeking asylum has her fingerprints taken by a U.S. Customs and Border Protection officer at a pedestrian crossing from Mexico to the United States, in McAllen, Tex., on May 10. (Carlos Barria/Reuters)

A group of immigration lawyers and advocates filed a class-action lawsuit Wednesday against Homeland Security Secretary John F. Kelly and other top U.S. officials, alleging that guards along the U.S.-Mexico border have systematically violated the law by turning away people who are seeking asylum.

The lawsuit filed in U.S. District Court in California alleges that U.S. Customs and Border Protection officials have used a range of tactics to deny people their right to state their fears of persecution and apply for asylum, including “misrepresentations, threats and intimidation, verbal abuse and physical force.”

In some cases, the complaint alleges, CBP officials have told people that “Donald Trump just signed new laws saying there is no asylum for anyone.” In other instances, border guards have allegedly threatened to take away the foreigners’ children unless they signed forms forgoing their asylum claims or said on camera that they had no fear of returning home.

“CBP has been emboldened by the anti-immigrant rhetoric around the election. They are flagrantly breaking the law,” said Erika Pinheiro, the policy and technology director at Al Otro Lado, a legal aid organization based in Los Angeles that is one of the plaintiffs in the suit. “They have either been told, or believe, that there should be no more asylum seekers.”

The United States has long adhered to international law allowing people to seek asylum if they are being persecuted because of their race, religion, nationality, political beliefs or other factors. If foreigners entering the United States express a fear of being returned to their home country, Border Patrol officers are required to process them for an interview with an asylum officer, the Department of Homeland Security said in a statement on Tuesday, before the lawsuit was filed.

A U.S. Border Patrol vehicle shines its headlights towards the U.S-Mexico border fence at dawn, as seen from Tijuana, Mexico, in May. (John Moore/Getty Images)

“As we continue to work toward protecting our borders, CBP has not changed any policies affecting asylum procedures,” the statement said.

But over the past year, immigration lawyers and advocates have documented hundreds of cases of asylum seekers, often from Mexico and Central America, being turned away at the border. Groups such as Amnesty International and Human Rights First say such incidents have occurred at crossings along the 2,000-mile border with Mexico. There has been a surge in asylum cases in recent years, particularly involving Central Americans, amid rampant gang violence in countries like El Salvador and Honduras. The numbers, have fallen off since Trump’s inauguration, however, as fewer migrants are attempting to cross.

In January, immigrant advocates filed a complaint with Homeland Security’s Office for Civil Rights and Civil Liberties alleging a “systemic” practice of turning away asylum seekers. Migrants who are denied interviews are often forced back into dangerous circumstances in Mexico or Central America.

The plaintiffs suspect that pattern of rejections stems from some change in policy, and they hope that the legal process may shed light on whether senior Homeland Security or border officials have issued orders that resulted in asylum seekers being turned away.

“Our organization has documented this over 100 times,” Pinheiro said. “It would be very strange if there's that many rogue officers that are all doing the same thing at different ports of entry.”

The lawsuit, filed by Al Otro Lado and six individuals who are represented by the American Immigration Council, the Center for Constitutional Rights, and the law firm of Latham and Watkins, argues that top U.S. officials have violated the U.S. Immigration and Nationality Act, which says that any foreigner who reaches the United States has the right to apply for asylum. The complaint also alleges a violation of international law and of the asylum seekers’ constitutional right to due process.

Several of the plaintiffs are Mexican and Central American citizens who fled to the United States to escape violent drug cartels and gangs. The complaint describes several cases in which CBP officials allegedly coerced asylum seekers into signing false statements or recanting their fears on video, or allegedly provided false information — such as that Mexicans are no longer eligible for asylum, or that the United States was no longer accepting migrant mothers and children.

One Honduran woman and her 18-year-old daughter had been “repeatedly raped by MS-13 gang members,” the Central American gang that Trump has highlighted for its brutality, according to the suit. But CBP officials “misinformed” them about their rights and denied them a chance to apply for asylum at the Tijuana-San Diego crossing, the suit alleged. A Mexican woman who had been abducted and threatened by drug cartel members was told by one CBP official in San Diego that her “children would be taken away” if they allowed her into the United States to apply for asylum, according to the suit.

In recent months, other asylum seekers at Tijuana were told by U.S. border guards that if they wanted to get processed, they needed to sign up with Mexican immigration authorities first, according to interviews with migrants and advocates. But the Mexican officials ultimately wouldn't handle their cases. This was an issue of particular concern to Mexicans trying to flee their own country.

“They’re getting very creative; we keep hearing new ways they’re turning people away,” said Kathryn Shepherd, a lawyer with the American Immigration Council, a Washington-based advocacy group.

Lawyers say that not all asylum seekers are rebuffed at the border. But, said Shepherd, “If a single asylum seeker is denied in a day, that’s one too many.”