MADRID - Around 421 people were sleeping rough at Madrid's airport in March, a survey by a Catholic charity group counted.
Most were men, half had been sleeping at the airport for over six months and 38 percent said they had a job.
Nearly all of them would leave the airport during the day.
The issue has exposed deep divisions among the institutions tasked with addressing homelessness.
City and regional governments in Madrid have clashed with Aena, which operates under the control of Prime Minister Pedro Sanchez's Socialist administration.
"Primary social care is the responsibility of the local government," Aena said in a statement, adding the city must fulfil its "legal duty to care for vulnerable populations".
Madrid's conservative Mayor Jose Luis Martinez-Almeida fired back, arguing that the central government controls Aena and "what's happening depends on several ministries".
The city insists that most of those sleeping in the airport are foreigners who should fall under Spain's international protection system.
Despite the finger-pointing, both sides have agreed to hire a consultancy to count and profile those sleeping at the airport. The study results are expected by the end of June.
Those who call Barajas home say the increased scrutiny in Europe's fifth busiest airport is unwelcome.
They doubt solutions will come and fear losing what they see as the safest place to sleep, compared to the streets or the metro in a city where homeless shelters have limited capacity.