Masked gunmen stormed a train in south-eastern Mexico and kidnapped at least 80 Central American migrants presumably bound for the US, a priest who runs a migrant shelter said.

The Rev Alejandro Solalinde said migrants who had escaped the attack had told him that armed men in ski masks and civilian clothes intercepted the train as it headed northwards through Veracruz state on Friday. The gunmen allegedly forced migrants to climb down from the top of the cars and bundled some into at least three waiting cars.

Solalinde, who runs a migrant shelter in nearby Oaxaca state, said he suspected the Zetas drug cartel of being involved because it operates in the area.

The train was scheduled to stop at the community of Medias Aguas in Veracruz but continued on to an isolated area, the witnesses told Solalinde..

The federal government's National Immigration Institute said it was assisting with an investigation by federal prosecutors and state officials in Veracruz and Oaxaca. Agents with Grupo Beta, a government-sponsored organisation that aids migrants, have gone to the area of the alleged kidnapping to look for witnesses, it said.

The priest said some of those who had escaped had told authorities about 250 migrants were on the train. Most of them were from Honduras and Guatemala.

Thousands of Central American migrants enter Mexican territory without permission each year, many bound for the US.

A report released in February by Mexico's National Human Rights Commission said at least 11,333 migrants were abducted between April and September 2010.

One of the worst attacks in recent history occurred in August 2010, when 72 migrants were killed in the northern state of Tamaulipas near the border with Texas. The Zetas are suspected in that killing.

Police also recently made arrests in the suspected December kidnapping of 50 migrants in Oaxaca.