EFEBy Juan Manuel Blanco Tapachula, Mexico

The deaths this week of 53 undocumented immigrants after spending hours trapped inside an overheated tractor-trailer in Texas were very much on the minds of the nearly 4,000 migrants who set out Friday from this city on the Guatemalan border with the aim of reaching the United States.

The new caravan, mainly comprising people from Central America and Venezuela, left Tapachula before dawn for Huixtla, some 52 km (32 mi) up the road, where they plan to ask for transit visas and transportation for the northbound journey.

The migrants are anxious to avoid the fate of the Mexicans and Central Americans who died in San Antonio, Texas.