The Latest on a caravan of Central American migrants hoping to reach the United States (all times local):

3:45 p.m.

The head of Mexico's federal police says the first two buses have arrived at the Mexico-Guatemala border crossing so that immigration officials can take women, children and seniors away to be processed safely.

Manelich Castilla tells Milenio TV it is part of their plan to process the 3,000 some migrants who are trying to enter Mexico from Guatemala.

But at the bridge migrants, who have formed orderly lines, are refusing to board the buses fearing that they will simply be deported.

Some are chanting "Walk! Walk!" insisting that they prefer to continue on foot.

Manelich also blamed people who were not part of the caravan for attacking police with powerful firecrackers and rocks.


1:55 p.m.

Cristian, a 34-year-old cell phone repairman from San Pedro Sula, Honduras, says he wants to reach the U.S. to work.

He declined to give his last name, because he was threatened by gang members who demanded he pay 2,000 lempiras, about $83, per month for protection. That would be about one fifth of his income. He closed his small business instead. He can't support his four daughters on the $450 that he makes each month.

Cristian, who is among the informal leaders of the caravan, estimated about 30 percent of the migrants want to apply for refugee status in Mexico. The rest want to reach the U.S. like him.

"Honestly, I want to get to the states to contribute to that country, to do any kind of work, picking up garbage," he said.


1:34 p.m.

The head of Mexico's federal police says that they have achieved their first objective of preventing a violent breach of the border by some 3,000 migrants trying to enter from Guatemala.

Manelich Castilla told Foro TV the migrants will enter in an orderly fashion.

"It will be under the conditions that have been said since the start: orderly, with established procedures, never through violence nor by force," Castilla said from the Mexican border town of Ciudad Hidalgo.

Police deployed pepper spray after some migrants tried to push their way through the Mexican side.

Some migrants are now forming lines on the bridge while others are sitting down and preparing for a long wait.


12:55 p.m.

Central American migrants in a mass caravan have clashed with Mexican riot police guarding a border post on the country's southern frontier.

About 50 migrants managed to push their way through. The rest retreated after officers unleashed pepper spray. Some in the caravan threw rocks.

After police held off the migrants, they closed the border gates again.

A federal police officer used a loudspeaker to address the masses, saying: "We need you to stop the aggression."


12:10 p.m.

Migrants in a caravan traveling through Central America have broken down gates at a border crossing and are streaming toward a bridge to Mexico.

After arriving at the tall, yellow metal fence Friday, some clambered atop it and on U.S.-donated military jeeps.

Young men began violently tugging on the barrier and finally succeeded in tearing it down.

Men, women and children then rushed through toward the bridge, about 150 yards (137 meters) away.


11:30 a.m.

Migrants in a mass caravan are chanting that "one way or another, we will pass" as they move toward a bridge on the Guatemala-Mexico border.

The caravan of disorganized women, men and children headed toward the border post Friday morning.

They got as far as a closed metal gate where two military jeeps were parked and Guatemalan police in riot gear looked on silently.

The migrants also chanted: "We are not smugglers, we are immigrants."

Dozens of Mexican federal police officers were on the bridge, with hundreds of others behind.

Mexico's ambassador to Guatemala said his country had decided to enforce a policy of "metered entry" in the face of the thousands clamoring to cross.


10:50 a.m.

Thousands of migrants traveling in a caravan briefly moved toward a border crossing on the Mexico-Guatemala frontier before turning around.

They stopped about two blocks from the crossing before heading back, saying they would wait another hour or so. Some of them talked among themselves.

The border post is guarded by a heavy security force and tall metal gates. Dozens of Mexican federal police officers are on the border bridge, with hundreds more behind them.

Guatemala has closed its border gate and is standing guard with dozens of troops and two armored jeeps.

Mexico's ambassador to Guatemala says his country has decided to enforce a policy of "metered entry" since thousands of migrants are clamoring to cross.

The migrants hope to enter Mexico and cross the country to reach the United States.

Jose Porfirio Orellana is a 47-year-old acorn and bean farmer from Yoro province in Honduras.

Orellana says "the economy in Honduras is terrible, there is nothing there."


7 a.m.

Participants in a 3,000-strong migrant caravan heading toward the United States have gathered in a park to wait a few more hours for members of the group who are still arriving.

The migrants have agreed that they will begin their journey to the border crossing between Guatemala and Mexico around 11 a.m. local time.

Some plan to make a valley-like formation, with men walking to the sides and women and children walking in the middle. Others intend to cross the Suchiate River on a raft.

The exhausted travelers are mostly from Honduras, but migrants from other Central American countries have joined the caravan.

Jonathan Guzman, a 22-year-old from El Salvador, said he had dreams of working in construction in Los Angeles.

"It's the third time that I'm trying to cross," he said.

As the sun rose, a military helicopter could be seen overhead, foreshadowing the difficulties that migrants will have as they try to reach the U.S.