For much of the summer, Nayelly Barrios has been making frequent trips to the US-Mexico border, bringing along backpacks stuffed with supplies to hand out to the immigrants waiting on the bridge that spans the Rio Grande river, connecting the United States and Mexico.

She finds those migrants and refugees waiting on the Mexico side, yearning to enter the US and ask for safety and shelter – although they are sometimes forced to wait days or weeks to set foot on American soil. Some have travelled hundreds or thousands of miles, and have acquired the requisite look of those who have completed a journey of biblical proportions such as that: tattered clothes, deteriorating shoes and a general lack of many belongings – even owning a small sleeping pad to cushion the bridge’s concrete at night is a luxury.

So Barrios hands out the backpacks – filled with clothes, food or other supplies she and other volunteers with the group Angry Tias and Abuelas (Angry Aunts and Grandmas) pack up in a Presbyterian church in Harlingen, Texas – to help them feel a bit more comfortable, and perhaps a bit less hungry.

“We took a lot of flip flops, and they were just so happy to be out of their tennis shoes and socks,” Barrios says, recalling her first supply trip to the border in June. “They were things that usually you wouldn’t be so overjoyed by, but they needed them so badly.”

The group Barrios helped establish to ease a border crisis made worse by punitive American immigration policies is one of many that have formed or flocked to southern Texas as part of a growing army of volunteers keen on helping those who have been hit by President Donald Trump’s crackdown at the border.

The groups encompass a range of experiences, and come from all over – the Tias, as they refer to themselves in short hand, are comprised of local activists, while others are coming from every corner of the US, hoping to lend a hand.

People strike across America for A Day Without Immigrants Show all 16 1 /16 People strike across America for A Day Without Immigrants People strike across America for A Day Without Immigrants Demonstrators march during the "Day Without Immigrants" protest in Chicago, Illinois, February 16, 2017. Theopolis Waters/Reuters People strike across America for A Day Without Immigrants Demonstrators march during the "Day Without Immigrants" protest in Washington, DC, U.S., February 16, 2017. Aaron P. Bernstein/Reuters People strike across America for A Day Without Immigrants Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. The crowd, which grew to well over a thousand participants, marched from the Austin City Hall to the Texas State Capital. Across the country hundreds of restaurants and eateries are closing for the day to protest President Trump's immigration policies and to highlight the contributions of immigrants to U.S. business and life. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants AUSTIN, TX - FEBRUARY 16: Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants Demonstrators march during the "Day Without Immigrants" protest in Chicago, Illinois, February 16, 2017. Theopolis Waters/Reuters People strike across America for A Day Without Immigrants Demonstrators march during the "Day Without Immigrants" protest in Chicago, Illinois, February 16, 2017. Aaron P. Bernstein/Reuters People strike across America for A Day Without Immigrants Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. The crowd, which grew to well over a thousand participants, marched from the Austin City Hall to the Texas State Capital. Across the country hundreds of restaurants and eateries are closing for the day to protest President Trump's immigration policies and to highlight the contributions of immigrants to U.S. business and life. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants Protesters march in the streets outside the Texas State Capital on 'A Day Without Immigrants' February 16, 2017 in Austin, Texas. The crowd, which grew to well over a thousand participants marched from the Austin City Hall to the Texas State Capital. Across the country hundreds of restaurants and eateries are closing for the day to protest President Trump's immigration policies and to highlight the contributions of immigrants to U.S. business and life. Drew Anthony Smith/Getty People strike across America for A Day Without Immigrants High school student Kathia Suarez holds up a sign as she protests with others outside the Grayson County courthouse in downtown Sherman, Texas, Thursday, Feb. 16, 2017. LM Otero/AP People strike across America for A Day Without Immigrants High school senior Vicky Sosa holds a sign outside the Grayson County courthouse in downtown Sherman, Texas, Thursday, Feb. 16, 2017. In an action called "A Day Without Immigrants," immigrants across the country are expected to stay home from school, work and close businesses to show how critical they are to the U.S. economy and way of life. LM Otero/AP

For the Tias, that organising grew alongside reports that the Trump administration had implemented plans that led to thousands of immigrant children being separated from their parents as part of a “zero tolerance” policy for illegal border crossings.

One such group, Grannies Respond, has organised caravans that embarked from New York City and elsewhere just this week to cross thousands of miles in order to help the newcomers at the American border.

And yet another, the Veterans Service Corps – a group originally founded to help fight back against a proposed pipeline at the Standing Rock Native American Reservation in North Dakota in 2016 – have reimagined their previous purpose and are now helping those immigrants standing under the blaring sun in Texas.

Brandon Boucher, with the Veterans Service Corps, says that his group has been in touch with different organisations on the border, and has developed what is essentially a three-pronged strategy for their involvement. At the border itself, Boucher says they plan on organising veterans to literally walk immigrants past Border Patrol agents and onto US soil where they can then legally claim asylum. Doing so, he says, would solve a couple of problems identified by activists at the border – for example the fact that some families are taking dangerous alternate trips to get across the border.

The group of veterans have also decided to help deported veterans who served in the US military without American citizenship, and who, he says, often suffer from PTSD. “There are combat veterans who have served in the US armed forces for a path to citizenship, who have served combat tours in Iraq and Afghanistan, and have been discharged honourably from the military, and then scooped up by Immigration and Customs Enforcement (ICE) and actually deported,” Boucher says.

Beyond that, they’re planning on helping find sponsors for families coming to the US, and raising money to help with what can be steep costs and conditions associated with travel to those sponsors once the immigrants are released from federal detention – as are the Tias.

Although some of the groups are basically in nascent stages, the success of their organising has been fast and impressive.

That growth and success is probably best seen in the case of the Tias, who first began organising in June when a few of the women started messaging on Facebook, and then decided to work together to bring supplies to the immigrants, both at the border and before they get on their buses to travel to their sponsors – trips that can take days at times, and present considerable challenges for immigrants who have just arrived in a foreign country, oftentimes do not speak the dominant language and don’t understand their itineraries to begin with.

Cindy Candia-Luna, another one of the Tias, said that the support their efforts have received has been massive. Soon after they first brought supplies down, Candia-Luna contacted the bilingual media platform Neta, and asked for help setting up a GoFundMe account to crowdsource funding for their efforts. The results shocked her, and the account ultimately raised around $70,000 (£53,800) – a figure that is too much for their efforts, so they have diverted some of that cash to shelters in Mexico.

And Candia-Luna gives no indication that she plans on slowing down her efforts if she can help it.

“These are human beings. The government is treating them less than, and they are not less than,” she says.