San Juan Mayor Carmen Yulín Cruz on Tuesday lauded FEMA efforts in hurricane-battered Puerto Rico and dismissed President Trump's tweets about the nation's massive debt as unrelated to the island's deepening humanitarian crisis.

"Make no mistake, there is a humanitarian crisis," Cruz told CNN. "There are thousands and thousands of people going back to their homes to find out they don't have a home to go back to."

Cruz said, however, that aid was starting to reach the island, and "that is making people feel like we're not alone and we can make it," Cruz said, adding "FEMA people have been wonderful."

That drew an almost immediate Twitter response from Trump: "Thank you to Carmen Yulin Cruz, the Mayor of San Juan, for your kind words on FEMA etc.We are working hard. Much food and water there/on way."

Trump also tweeted about Puerto Rico on Monday, saying that Texas and Florida are "doing great" after hurricanes Harvey and Maria. But he cited Puerto Rico's fragile infrastructure and massive debt in noting that the island was "in deep trouble."

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"These are two different topics," Cruz told CNN. "You don't put debt above people, you put people above debt.

Cruz said workers have been feverishly working to rescue islanders from the rubble. The island is struggling to regain power, and some water systems have failed. Bridges are out. Food and water is at a premium, she said.

The island is home to 3.4 million people, 60% of whom Cruz said lived below the poverty line before Hurricane Maria made its devastating hit last week.

In Punta Santiago, a town of about 5,000 people 40 miles southeast of San Juan, someone scrawled on a street in words the size of cars: "S.O.S. Necesitamos agua/comida!!" — We need water/food!!

"There is a moral imperative," Cruz said. "When someone is in need, when someone is in dire need, when someone is in a life or death situation, there is a human, moral imperative to deal with that situation before dealing with anything else."

Some bits of good news were emerging from the chaos. Gov. Ricardo Rosselló said Tuesday that airports in Aguadilla, Mercedita, Isla Grande, Ceiba and Vieques also were seeing limited service.

San Juan's Luis Munoz Marin International Airport was powering up after days without air conditioning, computers and radar equipment. A limited number of passenger flights were getting out, and vital aid flights were getting in.

Still, Rosselló stressed that Puerto Rico needs more help.

"Our ask to the (Trump) administration is, let's recognize that this is unprecedented and let's increase that support," Rosselló told MSNBC. "Or else it’s going to be a tough road ahead for the people of Puerto Rico."