MEXICO CITY - The number of illegal immigrants passing through Mexico on their journey to the United States increased by over 150 percent from 2013 to 2015, said an official on Wednesday.

The number of undocumented immigrants went from 86,000 in 2013 to 202,000 in 2015, Ardelio Vargas, commissioner of the National Institute for Migration, told lawmakers.

The number of minors among those immigrants increased by 344 percent between 2013 and 2015, he noted.

Most of the migrants are from Honduras, El Salvador, Guatemala and Nicaragua while more Africans, Haitians, Asians and Cubans are also arriving.

"Mexico has moved from a migrant-sending country to a migrant-receiving country, a situation which has become an intense problem," said Vargas.

He cited violence, poverty and drought in Central America for more illegal immigrant flow to Mexico.

The government will keep a close eye on the flow of illegal immigrants, Vargas said, adding all countries should work together to deal with the problem.

Mexico will try to contain the illegal flow through agreements with countries of origin, he added.

Mexico and the United States share a border of more than 3,000 km. Every year, some 318 million border crossings take place.