Twenty deportees from the United States arrived in Liberia on Thursday, as part of a new agreement that will see the west African country receive as many as 1,200 people under the Trump administration’s immigration crackdown.

The group arrived at the Roberts international airport outside the capital, Monrovia. The Liberia-US agreement is one of the largest third-country deportation arrangements pursued by the administration since Trump returned to office last year.

The Liberian information minister, Jerolinmek Piah said the 1,200 deportees will include African nationals as well as nationals from North America, South America and the Caribbean.

During a briefing on Tuesday, Liberia’s justice minister, Natu Oswald Tweh, said that the majority of the deportees had committed migration-related violations and offenses, and that they could seek asylum in the west African country if they wished.

The US has agreed to extend visitor visas for Liberians from 12 to 36 months and pledged $124m in assistance as part of the arrangement.

Under a series of often-secret agreements, the Trump administration has deported thousands of people to nearly two dozen countries that are not their own, advocates say, with about 10 of them in Africa. A new report by Refugees International and Human Rights First say the Trump administration has reached deals with at least 35 countries and has sent roughly 23,000 people to 26 of them as of early August, and makes the Liberia agreement the largest single arrangement so far.

Immigration lawyers have said the Trump administration uses deportations to third countries as a legal loophole to indirectly force asylum seekers back to their home countries.

In many cases, migrants are deported to countries they have never been to or where they face safety risks and are left with little choice other than to return to the home countries they were fleeing from.

A February report by Senate foreign relations committee Democrats found the Trump administration had paid more than $32m to five governments, several with poor human rights records, to accept about 300 third-country deportees – including $1.1m per person to Rwanda for seven deportees, and $7.5m to Equatorial Guinea for 29, a sum exceeding all US aid to that country over the previous eight years.

The report found more than 80% of those sent to third countries had since returned home anyway, often at further cost to taxpayers, and cited cases where deportees with US court-ordered protections were removed to Ghana and Equatorial Guinea before being sent onward within days.

The state department disputed the report’s characterization of its enforcement record.

The Associated Press contributed reporting