Migrants walk along the road after Mexico's federal police briefly blocked the highway in an attempt to stop a thousands-strong caravan of Central American migrants from advancing outside the town of Arriaga, Chiapas state, Mexico, Saturday, Oct. 27, 2018. Hundreds of Mexican federal officers carrying plastic shields had blocked the caravan from advancing toward the United States, after several thousand of the migrants turned down the chance to apply for refugee status and obtain a Mexican offer of benefits. (AP Photo/Rebecca Blackwell)