CIUDAD JUAREZ, Mexico — For thousands of desperate asylum seekers, there are many ways to wait — and wait, and wait — at the threshold of the United States.

Parents and children sleep in tents next to bridges leading into Texas for weeks on end, desperately hoping their names and numbers are called so they can be let in.

Some immigrants complain of shakedowns and kidnappings by gangs and corrupt officials. Others pay bribes to get to the front of the line; the rest, determined to enter the country legally, wait patiently, even if it takes months.

This is what has happened since the Trump administration placed asylum in a chokehold.

The Associated Press visited eight cities along the U.S.-Mexico border and found 13,000 immigrants on waiting lists to get into the country — exposed to haphazard and often-dubious arrangements that vary sharply.

The lines began to swell in the last year when the administration limited the number of asylum cases it accepts each day at the main border crossings, leaving it to Mexican agencies, volunteers, nonprofit organizations and immigrants themselves to manage the lines.

In some cities, days pass without anyone being processed, the AP found. In San Diego, up to 80 are handled each day, but the line in Tijuana, across the border, is the longest anywhere — about 4,800 people.

Each day at each crossing, U.S. Customs and Border Protection officials alert Mexican counterparts how many people they will take — a system the government calls metering. Then the keeper of the list lets immigrants know who can go into the U.S. for asylum interviews.

A federal lawsuit says the administration is violating U.S. and international law by refusing to take asylum seekers when they show up at a crossing. U.S. authorities argue that processing capacity dictates how many people it can handle.

“It’s not turning people away, it’s asking them to wait,” then-Customs and Border Protection Commissioner and current acting Homeland Security Secretary Kevin McAleenan said in October.

But some feel they cannot. They try to enter illegally, sometimes with tragic consequences.

A Honduran family, arriving at Piedras Negras, Mexico, decided the line was too long. Crossing the Rio Grande, they were swept away; a father and three children, including a baby, are believed to have died.

Here is a snapshot of the wait list systems along the border:

CIUDAD JUAREZ: Black ink, wristbands, and thousands in line

The sprawling industrial city began its waiting list in October when many Cuban asylum seekers began sleeping on the narrow sidewalk of a busy international bridge. Mexican authorities decided they had to go.

Asylum seekers were then registered and had numbers written on their arms in black ink to show their number in line.  That was abandoned in favor of plastic wristbands, which were scrapped because so many people were selling or counterfeiting them. Now it’s a digital-based system.

There are currently about 4,000 names on the list.

REYNOSA: ‘River owners’ run the show

The challenges faced by asylum seekers waiting in Reynosa, across from McAllen, Texas, are compounded by rampant violence.  Gunfights between cartels and police occur daily, and the U.S. State Department has warned Americans not to travel there. Few Americans are willing to visit the shelter that controls the list or the other churches and hotels where asylum seekers wait.

Jennifer Harbury, a longtime human rights advocate in Texas, spoke recently to a large group of asylum seekers at the Senda de Vida shelter and met with people who had been kidnapped by cartels.

“The owners of the river, you know who they are,” Harbury said. Several nodded.

PIEDRAS NEGRAS, MEXICO: The WhatsApp List

When asylum seekers arrive at a migrant shelter in Piedras Negras, they are given a phone number to text on the messaging service WhatsApp. They’re supposed to send the names and photos of everyone in their group. Then they’re told to wait.

Managing the list is a local restaurateur named Hector Menchaca, who also serves as the local government’s liaison to U.S. Customs and Border Protection.

About 360 people are on the list, with another 200 people waiting to join it because the government has closed it to new entrants for the time being, Menchaca said.

The list includes people from Central America, Mexico, Brazil, and countries an ocean away like Cameroon. They aren’t told how close to the top they are, only that they might wait for two or three months.

But many people say they can’t wait — among them the four who are believed to have drowned in the Rio Grande last week.

NOGALES: A family affair

A woman whose family manages shelters in Nogales keeps the list of new arrivals in Nogales.

Before she was involved, Brenda Nieblas says hundreds of migrants would wait at the border crossing and many would try to rush in when U.S. authorities called people for processing.

When they first arrive, some of the migrants are sent to a Red Cross first aid station. They are then connected with Nieblas, who puts them on the list, assigns them to a shelter in Nogales and notifies them when their time comes.

TIJUANA and MEXICALI: A notebook, and waiting for the phone call

Tijuana is most experienced with a numbering system, having established one in 2016 when Haitians had to wait in Mexico for a chance at refuge in the United States. Its waiting list stands at about 4,800.

Grupos Beta, a unit of Mexico’s immigration agency that provides food, transportation and aid to migrants, keeps guard at night over tattered notebooks and hands them over to volunteers during the day to register new arrivals. On a recent Saturday, there were nearly 100 people in line to get a spot in the notebook — almost exclusively Cameroonians who arrived the previous day.

In nearby Mexicali, Grupos Beta employees in bright orange shirts call out those whose numbers are up. Mexicali — a city of about 1 million across from Calexico, California — has about 800 names on its list.