Transcript for Millions desperate for food, water and fuel in Puerto Rico

Thanks for joining us on this Sunday. I'm Tom llamas. We begin tonight with the growing H growing humanitarian crisis in Puerto Rico. FEMA now approving millioing app collation applications for assistance. Alex Perez starts us off. Reporter: Tonight, as supplies and other necessities trickle in to San Juan, people living just 25 miles away wondering if they've been forgotten. Nobody. Reporter: Nobody has come to help? No. Reporter: The Reyes family, in an isolated part of comerio, say they have been fending for themselves. 11 days now, no power, no cell service, no easily available drinking water. The hurricane ripping the roofs right off in this sprawling valley community. The river water now their means of bathing and cleaning up what's left of their homes. What's the hardest part? The babies. Reporter: There's no water to drink? No. Reporter: Very little. But in another small town, juncos, aid from FEMA finally arriving. It's not enough, it's not fast enough. They know that, we know that. Reporter: In San Juan, where lines at gas stations go on for blocks, fuel trucks now being escorted by armed officers. We have no food, we have no water. Buildings are becoming human prisons, human cages. Reporter: More help already on the way. Cargo ships filled with supplies. The massive Navy hospital ship comfort arriving this week. 6,400 troops already on the ground. With communications crippled, the general now in charge of military operations here, says the challenge is finding where the needs are so they can be met. We are not satisfied with what we've been able to do right now. These people deserve more help and we're going to bring it. Alex, power still such a major issue. Much of the island in the dark or on generators. And you have a new, alarming estimate of when the power will be back for the entire island? Reporter: Officials say it could be a long six months before the island is back on the power grid. But the resilience here stands out. Everyone we've talked to says they're determined to rebuild. Tom? Six months, so difficult. Alex, thank you.

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