Anti-immigration protesters impeded the arrival of several buses transporting undocumented immigrants into a US Border Patrol station in Murrieta, California on Tuesday, some 60 miles north of San Diego.

The arrival of the group of Central American families had been decried by Murrieta’s mayor, Alan Long, who alleged that the group of immigrants, adults with their children numbering about 140 people, represented a public safety threat to the community.

Assembled protesters, who numbered 150, converged on a street leading up to an access road into the processing center, preventing the two buses from reaching the facility, reported Reuters.

Police at the scene did not attempt to break up the demonstration, which included picket signs with messages such as “Return to sender” and “Bus illegal children to the White House,” and anti-immigration slogans. Almost a half hour into the incident, the two unmarked buses turned around and left.

A representative of the border patrol agents union said that the immigrants would likely be rerouted to one of the other six Border Patrol stations in the San Diego region. Local news reports seemed to confirm that the 140 undocumented immigrants were instead being driven to the Chula Vista Border Patrol facility in San Diego County.

The Central American immigrants had been flown to San Diego from Texas, and were on their way for processing at the Murrieta facility where US immigration officials told Reuters they would be released under supervision and await deportation.

Tuesday’s incident in Murrieta highlights the influx of both families and unattended minors from Central America, which have strained the border patrol’s resources and led to the creation of several temporary processing facilities to deal with overflow conditions in Texas.

BREAKING: Protestors blocking buses bringing undocumented immigrants to #Murietta Border Patrol center. @myfoxlapic.twitter.com/U5ttdBQuMG — Gigi Graciette (@GigiGraciette) July 1, 2014

Unlike undocumented immigrants from Mexico, who are subject to immediate deportation, the latest influx of families and children feeling violence and poverty in Guatemala, El Salvador and Honduras are instead subject to processing by authorities.

Unaccompanied minors are the responsibility of the US Department of Health and Human Services, which is currently scrambling to create enough housing and provide basic care. Some 500,000 unattended children have crossed into the US illegally within the past year alone. The agency’s program, Unaccompanied Alien Children (UAC), was only meant to serve the needs of some 8,000 children per year while being processed through US immigration court.

Temporary facilities have been set up in Nogales, Arizona to cope with overflow from South Texas. Meanwhile, another group of immigrants had been driven to a similar facility in El Centro, California, some 100 miles east of San Diego.