SAN DIEGO—U.S. Border Patrol agents arrested 32 people at a demonstration Monday that was organized by a Quaker group on the border with Mexico, authorities said. Demonstrators were calling for an end to detaining and deporting immigrants and showing support for migrants in a caravan of Central American asylum seekers.

A photographer for The Associated Press saw about a dozen people being handcuffed after they were told by agents to back away from a wall that the Border Patrol calls “an enforcement zone.” The American Friends Service Committee, which organized the demonstration, said 30 people were stopped by agents in riot gear and taken into custody while they tried to move forward to offer a ceremonial blessing near the wall.

Border Patrol spokesman Theron Francisco said 31 people were arrested for trespassing and one was arrested for assaulting an officer.

More than 300 people, many the leaders of churches, mosques, synagogues and indigenous communities, participated in the demonstration at San Diego’s Border Field State Park, which borders Tijuana, Mexico.

The rally held on a beach divided by the border wall was the second confrontation for Border Patrol agents since a caravan of more than 6,000 migrants, predominantly Hondurans, reached Tijuana last month. A confrontation with rock-throwers from Mexico led to U.S. agents firing tear gas into Mexico on Nov. 25 and a five-hour closure of the nation’s busiest border crossing.

Thousands of migrants are living in crowded tent cities in Tijuana after undertaking a grueling journey from Central America to the U.S. border. Many face waiting weeks or months in Mexico while they apply for asylum. The U.S. is processing up to about 100 claims a day at the San Diego crossing, which is creating a backlog.

The demonstration Monday was meant to launch a national week of action called “Love Knows No Borders: A moral call for migrant justice,” which falls between Human Rights Day on Monday, and International Migrants’ Day on Dec. 18, the group said.

“Showing up to welcome and bless children, mothers and fathers seeking asylum from very difficult and dehumanizing circumstances is the right and humane thing to do,” said Bishop Minerva G. Carcano, from the San Francisco Area United Methodist Church. “How we act in these moments determines who we will become as a nation.”

The group also is calling on Congress to defund Immigration and Customs Enforcement and Customs and Border Protection.