The migrant caravan that caught the attention of the White House arrived at the Mexican border this week with hopes that their individual cases would be heard and they could be granted political asylum in the United States.

About 150 immigrants, mostly from Honduras, El Salvador and Guatemala, reached the San Ysidro International Border, marking the end of the line for a journey that began in late March in Tapachula, Chiapas, Mexico. They are now being processed a few at a time by Customs and Border Protection officers.

Migrants were told at first that they would have to wait in Mexico, stating that the Port of Entry was at capacity due to a higher-than-expected number of undocumented immigrants who had arrived days earlier for the same purpose. While they awaited their turn, the group camped just outside the port of entry.

“We are encouraging asylum seekers to seek asylum in the first safe country they enter. However, we will process asylum claims in accordance with the law,” said a San Diego CBP spokesperson.

By Wednesday afternoon, advocates accompanying the caravan had counted 74 individuals, the majority of whom were mothers and their children, who had been allowed in for processing by CBP, which means close to half of the caravan has now been received.

“CBP will continue to work with its interagency partners at ICE to ensure continued management of persons presenting without documents and appropriate care and custody of all those in our facility.”

The migrants fled to escape violence in their home countries. Many tell of extortion and being threatened by gang members, including those belonging to MS13.

Once they inform the CBP officer that they fear returning home, they are assigned an asylum officer who must then interview them in order to determine if there is a believable threat of “persecution and torture.”

If the officer finds that there is such a threat, the case is then referred to an immigration court. At that time, the individual may remain indefinitely at an immigration detention center or – in some cases – be granted a conditional release with a monitoring bracelet.

However, few asylum seekers are actually granted asylum by the U.S. Government.

According to Department of Justice statistics, of 65,218 petitions received in fiscal year 2016, only 8,726 were approved.

“Being an immigrant is not a crime, it is not breaking the law, and they come full of hope seeking political asylum, but also full of fear because under (President) Donald Trump they are jumping into the unknown,” said Lourdes Lizardi, a migrant advocate with Angels Without Borders.

While this is not the first migrant caravan to make the journey, this one gained visibility as a result of its being the target of criticism by President Trump, who called on the Mexican government to step in to keep the caravan from reaching the border.

During his visit to Calexico, California, Vice-President Mike Pence thanked the government of Mexico for their assistance, which led to a much lower number of asylum seekers making the journey than the many hundreds initially thought. Many others, however, were not discouraged, insisting that they had traveled to the border not because they wanted to, but because they had to.

“We are mothers, we are fathers, we are children who are the new future, and we beg to be heard, to be given an opportunity,” shared Linda Zuñiga, a grandmother from El Salvador who made the trip with her two children and her granddaughter.

Some advocates argue that the White House has used the caravan to push an anti-immigrant agenda, including the construction of the border wall.

“They have used a narrative of ‘invasion’, when we all know most of them are here to turn themselves in (for asylum)”, said American Friends Service Committee Director Pedro Rios, who stressed that the migrants in the caravan are following a process allowed by law.

By Thursday morning, activists who had joined the caravan had a count of 158 people, mostly mothers and their children, whom had been received by immigration authorities for processing.