Three Spanish firefighters who volunteered to help rescue refugees and migrants reach Greek islands have asked the European Parliament to back them as they face trial on charges of human trafficking for bringing the desperate people ashore.

They were working with the NGO Proemaid on the eastern Aegean island of Lesbos which has been overrun with refugees and migrants send there and other Greek islands by human traffickers that Turkey lets operate even during a suspended swap deal with the European Union that has seen only a relative handful ruled ineligible for asylum returned.

The rescuers, Seville firemen Manuel Blanco, Julio Latorre and Enrique Rodriguez, are set to stand trial on May 7 and could face up to 10 years in prison if found guilty of charges they say are based on a misunderstanding, Euronews reported.

“We are not smugglers. We are rescuers doing humanitarian work to help the local authorities who don’t have the capacity to help the huge number of Syrian refugees escaping the war,” Blanco told Euronews from Brussels, where he is trying to rally European lawmakers.

“If a person is drowning and you bring them ashore to try and save them, that can be seen as facilitating their entry,” he added. “How you can compare a person who smuggles people for money with rescuers who save people’s lives?”

Blanco told Euronews that he first came to Lesbos in 2015 at the peak of the refugee crisis and worked several missions until his arrest in January 2016 along with that of his two colleagues.

“I’ve been a firefighter for 20 years and I thought I had seen every sort of emergency response scenario but I hadn’t experienced a humanitarian crisis of this caliber,” he told the news site.

It wasn’t explained why the men were singled out among the hundreds of volunteers, NGO’s and rescuers helping refugees and migrants reach Greek islands, including those depicted in award-winning documentaries, Greek fishermen and Coast Guard personnel.

There are more than 15,000 refugees and migrants stuck on Greek islands, and another 50,000 in mainland detention centers and camps, stuck after the European Union closed its borders to them and reneged on promises to help take some of the overload.

Greece is trying to deal with an overwhelming number of asylum applications and pleaded for more EU help to deal with people who first reached Turkey from Middle Eastern countries, primarily Syria, fleeing war and strife and had hoped to move on to more prosperous countries before the door was shut on them.