Washington (CNN) Why is it taking so long to track down hundreds of parents who were deported from the US without their children after their families were separated at the border?

American Civil Liberties Union attorney Lee Gelernt told the court during a hearing in the ongoing family separations lawsuit that he had just returned from a trip to Guatemala to view the reunification efforts with his own eyes, and the situation is dramatic and heart-wrenching.

Between gangs, jungles, shoddy phone service and distrustful parents, the situation in Central America is incredibly complex as each and every one of these parents is tracked down.

Somewhere close to half of the deported parents have come to conclusions about whether to be reunited, with the choice about 2-to-1 in favor of not being reunified vs. being reunited in their home countries. But the remaining half are still being tracked down and communicated with about their options.

Gelernt described a process that is painstakingly slow to find some parents. Phone numbers go in and out of use based on parents' ability to pay for service and if they are "fleeing violence." Other times, they may be reached, but may not trust the person at the other end of the line.

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