In the dead of night, a Border Patrol bus tried once again today to find safe harbor for 140 Central American immigrants.

Fresh from their illegal crossing into Texas, mothers and children aboard three buses were turned away in Murrieta, California , as protesters blocked the road into town.

The immigrants had been sent to Murrieta because Border Patrol facilities in south Texas were jammed.

"[The] transfer of immigrants between Border Patrol sectors occurs on a regular basis to allow CBP [U.S. Customs and Border Protection] to manage flows and processing capability," the U.S. Customs and Border Protection said in a statement today. "The movement will allow the U.S. Border Patrol in less-congested areas to assist in processing family units from South Texas where we are seeing an influx of migrants crossing the border."

Related: Surge of children crossing border fills Lackland AFB.

Watch: See Border Patrol site housing 500 unaccompanied minors.

Because of the road blocked by protesters, federal authorities had to reroute the buses to a facility in San Diego.

"We would have 500 immigrants potentially on the streets of Murrieta, which we don't have the resources to handle," said Mayor Alan Long, who had told residents to complain to officials about the immigrants' pending arrival.

Town officials said they feared that Border Patrol would hold the immigrants only long enough to process them and then, as ABC News saw firsthand in McAllen, Texas, release them at local bus stations where they would be free to go wherever they want.

One woman named Melissa and her 5-year-old son had started in Honduras and then spent eight days on a bus through Mexico. The two crossed the Rio Grande by raft to McAllen, Texas, and then spent four nights in a Border Patrol processing center.

Before boarding a bus to Maryland, Melissa promised that she'd show up in a Baltimore court today at 10 a.m. per a Notice to Appear she received by CBP at the border. The facilities confirm addresses and contact information to keep track of people.

Many families were at the courthouse with their kids, but three hours passed and ABC News never saw Melissa. No one answered at the Maryland residence she'd shared with us, either.

The Department of Homeland Security said that about 20 percent of immigrants actually showed up at court hearings.