Leona Blankenstein couldn´t believe what she was hearing when the Libyan coastguard threatened to blast her small plane out of the sky. The German doctor was in a spotter aircraft for the rescue charity Sea-Watch when she encountered the Fezzan patrol boat as it picked up migrants in Maltese waters on October 25.

“Get away from Libyan territorial (waters), otherwise we´ll shoot you by SAM (surface-to-air) missiles,” warned the vessel, one of several Italy gave to Libya under a controversial EU-backed deal to stop migrants reaching Europe.

The Libyans brought the migrants onboard before scuttling their rubber boat with incendiary ammunition, according to Sea-Watch footage. “It happened in just seconds... Their behaviour is highly unpredictable, so you never know what they are going to do next,” she said.

The warning “was threat enough for me to leave the area immediately”, she added. The 2017 deal has faced renewed scrutiny since far-right Italian leader Giorgia Meloni´s government took office, adopting a hardline stance against asylum seekers rescued at sea.

Despite years of criticism by charities and human rights groups, Italy quietly renewed the accord earlier this month. Campaigners say nearly 100,000 people have been intercepted by the Libyans since the deal, under which Italy and the EU agreed to train and equip Libya´s coastguard.

The agreement was formed under pressure to manage huge numbers of refugees fleeing to Europe from conflicts in Syria, Iraq and Libya. It also followed a series of deadly shipwrecks, with a record 5,000 people dying or reported missing in the Mediterranean in 2016.

The European Commission has said the accord aims “to prevent the loss of life in the Mediterranean and at the same time to crack down on migrant smuggling and human trafficking networks”. Last year 2,062 were reported dead or missing, according to the International Organization for Migration (IOM).