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My cousin needs to a attend a conference in Cartagena very soon and he is very confused with planning his travel itinerary. The direct flights from India to Cartagena are very expensive and long.
He has a valid business US visa. He wants to travel from India via the USA to Cartagena. Can he return to the USA from Cartagena (JFK or EWR) and onward to India? Will there be any Immigration when he connects in JFK/EWR?
Since he has a valid visa, can he book the tickets via the USA, which saves him time and money?