People receive information about their flights at Luis Munoz Marin International Airport, in San Juan, on Sept. 24. (Hector Retamal/AFP/Getty Images)

Puerto Rico’s largest airport is in a crisis.

Hundreds of would-be-travelers remained stranded Monday at Luis Muñoz Marín International Airport in San Juan, where terminals are dark, air conditioning is out, and people are running out of water and food.

Days after Hurricane Maria devastated the island, the airport, which serves about 9 million passengers a year, is struggling to return to normal. Maria brought damaging winds of about 160 mph, triggering massive flooding and power outages, and leaving significant infrastructure damage.

Only 20 commercial flights were scheduled Monday in San Juan, twice as many as there were Sunday.

“We continue to operate with emergency plans so there is no air conditioning and certain services are limited,” the airport said in a statement.

Without electricity, airlines are barely functioning.

“No computer system makes it difficult for airlines to vet passengers and confirm their tickets,” Patricia Mazzai, a reporter for the Miami Herald who traveled Sunday from San Juan, said in a tweet. “Boarding passes are filled out by hand if you’re lucky to get one.”

Posted by Montalvo Peter on Sunday, September 24, 2017

Significant damage to the air traffic control system is complicating resources getting in, Brock Long, administrator of the Federal Emergency Management Agency said during an afternoon news conference. He said the hurricane also left significant damage to much of the infrastructure, from communications to the fuel systems.

The Federal Aviation Administration has implemented a slot system to manage the demand for ramp space at the airport and to safely separate aircraft in the air, the agency said.

The number of commercial flights allowed to operate will increase as the FAA restores radars, navigational aids and other equipment damaged during the storm. On Sunday, the San Juan airport handled nearly 100 total arrivals and departures, including the military and relief operations, the FAA said.

“FAA technicians are working around the clock to restore services, but because of the extent of the damage and challenges of the terrain where equipment is located, it’s difficult to determine a timeline for the full restoration of service,” the agency said in a statement.

Crews are getting to critical traffic air control infrastructure that was destroyed or disabled during the storm, bringing replacement systems by air and by sea. On Monday, technicians were using chain saws to clear a path to get a second long-range radar site at Pico del Este, inside a National Park.

The Transportation Security Administration said it has enough staff on the ground to conduct normal screening operations at all airports in Puerto Rico once they open. At San Juan, TSA staff are conducting normal screening operations, TSA spokesman Mike England said.

On social media, journalists and travelers describe the scene at the airport as chaotic, dire and inhumane. Some travelers said they were running out of money, food and water.

“Hundreds of people in the San Juan airport are waiting for a flight, please help them,” tweeted Keshia Fraticelli, a graduate student who is following the situation from Madrid.

“The island is facing months without electricity, it is like living in a third world country,” she said via email. The conditions are so bad that she expects her return flight to San Juan next week will be canceled. The airport is not receiving international flights until further notice.

Though there was food to purchase, some families couldn’t withdraw money from automated teller machines that remain out of service throughout the island. Families with children and elderly people were sleeping on the floor waiting for flights out.

Gov. Ricardo Rosselló said Monday that he had authorized delivery of food and water to those stranded at the airport.

Airlines, meanwhile, were urging travelers to leave for the airport only if they have confirmed their flights. The damage and space constraints at the San Juan airport continue to limit the number of flights commercial airlines can operate.

United has not resumed revenue flights to Puerto Rico, he said. The airline has sent three relief flights since Saturday with food, water, blankets, and power generators, as well relief items for the American Red Cross.

“The conditions on the ground are tenuous and challenged by a lack of power, transportation and hotels,” United spokesman Frank Benenati said Monday afternoon.

Delta Air Lines said it was planning to operate two round trip flights to San Juan on Monday, after having only one trip Sunday. Delta is expected to operate three round-trip flights Tuesday.

Delta brought 80 Red Cross volunteers on a humanitarian flight to San Juan on Saturday, along with relief supplies and water.

Operating out of San Juan was a “logistical nightmare” under the current conditions, the airline told CBS News Correspondent David Begnaud.

The San Juan airport was leading in the number of cancellations Monday, with 88 departures and nearly 100 arrivals canceled Monday, according to the online site FlightAware.