"We will go to the northern border, comrades, with documents, without documents, with buses, without buses," incites activist Luis Vallega as thousands of migrants rest in the city of Huixtla after they left on June 6 from Tapachula, on Mexico's southern border, heading for the US. The migrants are awaiting an answer from the authorities on documents to freely cross the country, while the Summit of the Americas is being held in Los Angeles, with migration issues at the centre of the agenda. IMAGES AND SOUNDBITES