PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 25: Migrants cross the nearly dry Tijuana River as they make their way around a police blockade toward the El Chaparral port of entry on November 25, 2018 in Tijuana, Mexico. U.S. Customs and Border Protection temporarily closed the two ports of entry on the border with Tijuana in response. Around 6,000 migrants from Central America have arrived in the city with the mayor of Tijuana declaring the situation a 'humanitarian crisis'. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 25: A U.S. Marine helicopter patrols above a migrant waving the Honduran flag while gathered atop a train car near the U.S.-Mexico border fence on November 25, 2018 in Tijuana, Mexico. Migrants made their way to the location along the border after circumventing a police blockade as they attempted to approach the El Chaparral port of entry. U.S. Customs and Border Protection temporarily closed the two ports of entry on the border with Tijuana in response. Around 6,000 migrants from Central America have arrived in the city with the mayor of Tijuana declaring the situation a 'humanitarian crisis'. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 25: Migrants stand atop a train car in front of the U.S.-Mexico border fence on November 25, 2018 in Tijuana, Mexico. Migrants made their way to the location along the border after circumventing a police blockade as they attempted to approach the El Chaparral port of entry. U.S. Customs and Border Protection temporarily closed the two ports of entry on the border with Tijuana in response. Around 6,000 migrants from Central America have arrived in the city with the mayor of Tijuana declaring the situation a 'humanitarian crisis'. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 25: Migrants cross the nearly dry Tijuana River as they make their way around a police blockade toward the El Chaparral port of entry on November 25, 2018 in Tijuana, Mexico. U.S. Customs and Border Protection temporarily closed the two ports of entry on the border with Tijuana in response. Around 6,000 migrants from Central America have arrived in the city with the mayor of Tijuana declaring the situation a 'humanitarian crisis'. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 25: A U.S. Marine helicopter patrols above migrants gathered atop a train car near the U.S.-Mexico border fence on November 25, 2018 in Tijuana, Mexico. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 25: Mexican police stand guard (R) as migrants walk on a bank of the nearly dry Tijuana River as they make their way toward the El Chapparal port of entry, after circumventing a police blockade, on November 25, 2018 in Tijuana, Mexico. U.S. Customs and Border Protection temporarily closed the two ports of entry on the border with Tijuana in response. Around 6,000 migrants from the 'migrant caravan' from Central America have arrived in the city with the mayor of Tijuana declaring the situation a 'humanitarian crisis'. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 22: People waiting to cross the border in vehicles watch as U.S. Customs and Border Protection (CBP) agents conduct a "large-scale operational readiness exercise", which briefly closed the border crossing, on November 22, 2018 in Tijuana, Mexico. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 25: Migrants climb up a bank of the nearly dry Tijuana River as they attempt to make their way past a police blockade to the El Chapparal port of entry on November 25, 2018 in Tijuana, Mexico. U.S. Customs and Border Protection temporarily closed the two ports of entry on the border with Tijuana in response. Around 6,000 migrants from Central America have arrived in the city with the mayor of Tijuana declaring the situation a 'humanitarian crisis'. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 25: Migrants climb up a bank of the nearly dry Tijuana River as they make their way around a police blockade toward the El Chapparal port of entry on November 25, 2018 in Tijuana, Mexico. U.S. Customs and Border Protection temporarily closed the two ports of entry on the border with Tijuana in response. Around 6,000 migrants from Central America have arrived in the city with the mayor of Tijuana declaring the situation a 'humanitarian crisis'. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama PHOTOS: Migrants rush US/Mexico border to demand asylum TIJUANA, MEXICO - NOVEMBER 25: Migrants climb up a bank of the nearly dry Tijuana River as they attempt to make their way past a police blockade to the El Chapparal port of entry on November 25, 2018 in Tijuana, Mexico. U.S. Customs and Border Protection temporarily closed the two ports of entry on the border with Tijuana in response. Around 6,000 migrants from Central American 'migrant caravan' have arrived in the city with the mayor of Tijuana declaring the situation a 'humanitarian crisis'. (Photo by Mario Tama/Getty Images)Photo by: Mario Tama