Human Rights Watch on Wednesday accused Lebanon's army and the authorities in nearby Cyprus of working together to keep refugees out of Europe and deporting them to war-torn Syria.
Lebanon's army has intercepted Syrian refugees trying to leave by boat, "pulled them back, and summarily expelled them to Syria", the rights watchdog said in a statement launching a report.
"In tandem", Cypriot security forces including the coastguard "have sent Syrians whose boats reached Cyprus back to Lebanon, without regard to their refugee status or risk of being expelled to Syria", it said.
"Many of those sent back to Lebanon by Cyprus were immediately expelled to Syria by the Lebanese army," it added.
Contacted by AFP, the Lebanese army declined to respond, while the government of Cyprus was unavailable for comment.
Lebanon, which has been mired in a crushing economic crisis since late 2019, says it hosts some two million Syrians, the world's highest number of refugees per capita, with more than 774,000 registered with the United Nations.
The eastern Mediterranean island of Cyprus is less than 200 kilometers (125 miles) from the Lebanese and Syrian coasts, and has long been a route for refugees seeking a better life in Europe.
In May, the European Union approved $1 billion in aid for Lebanon to help stem irregular migration to the bloc.
HRW's Nadia Hardman said in the statement that Lebanon was violating "the fundamental prohibition on returning a refugee to face persecution, while the European Union helps pay the bills".
"Cyprus also violates this prohibition by pushing refugees back to Lebanon where they risk being sent to danger in Syria," she added.
Cyprus Interior Minister Constantinos Ioannou told HRW that "in 2020, Cyprus and Lebanon re-endorsed their mutual agreement" on migrants attempting sea crossings from Lebanon.
"There were several cases, when boats were intercepted and sent back to Lebanon for further management, in respect of our agreement," he said, according to the group's report.
Lebanon's General Security agency told HRW that any "expulsion or deportation" of Syrians or other migrants by Cyprus that it was involved with "was subject to international human rights law standards".
HRW said the Lebanese army had not responded to requests for comment on its findings, and the force told AFP it declined to comment.
Syria's war erupted in 2011 after the government repressed peaceful pro-democracy protests, and has killed more than half a million people and displaced around half of the pre-war population.
In May, Cyprus said it was among at least eight EU members who want so-called safe zones declared in parts of Syria.
Rights groups have repeatedly warned that Syria is unsafe for refugee returns.
