(AP) — Mexican authorities say group of mainly Central American migrants attempting to walk across southern Mexico has dwindled to less than a thousand. Mexico’s National Immigration Institute said Wednesday it had given humanitarian visas to about 800 migrants who were once part of the group. It says fewer than a thousand migrants continue with the group, which is now in the southern state of Oaxaca. The migrants once numbered as many as 4,000. But since they set out from the city of Tapachula on Oct. 23, the group has managed to make it only about 190 miles (310 kilometers).