MEXICO CITY (AP) — Mexican authorities said a group of about 350 migrants broke the locks on a gate at the Guatemalan border Friday and forced their way into southern Mexico to join a larger group of migrants trying to make their way toward the United States.

The National Immigration Institute did not identify the nationalities of the migrants, but they are usually from Central America.

A similar confrontation occurred on the same border bridge between Mexico and Guatemala last year.

The institute said the migrants were acting in a "hostile" and "aggressive" way, and accused them of also attacking local police in Metapa, a Mexican village that lies between the border and the nearby city of Tapachula.

The group of 350 pushed past police guarding the bridge and joined a larger group of about 2,000 migrants who are walking toward Tapachula in the latest caravan to enter Mexico.

Claudia Jaqueline Sandoval, 43, from El Progreso, Honduras, was walking toward Tapachula with her 6-year-old daughter. Another son and a daughter are already in the United States.

"I have been HIV positive for 16 years," said Sandoval, but her reason for going north was not just medical treatment. "It has been two years since I heard from my son" in the United States, and money is scarce, she said.

There are already several groups of migrants in the southern border state of Chiapas who have expressed frustration at Mexico's policy of slowing or stopping the process of handing out humanitarian and exit visas at the border.

A group of several hundred Cuban, African and Central American migrants have been waiting at the immigration offices in Tapachula for documents that would allow them to travel to the U.S. border, where most plan to request asylum.

Some members of that group have scuffled with immigration authorities and broken windows at the offices in recent days, accusing officials of making them wait too long for papers.

And another group of an estimated 2,500 Central American and Cuban migrants have been stuck for at least a week further west in the Chiapas town of Mapastepec, also waiting for papers.