An American father and son wanted for helping the former Nissan chairman Carlos Ghosn escape Japan in a box were handed over to Japanese custody on Monday, ending a months-long battle to stay in the US. Michael Taylor and his son, Peter Taylor, failed to convince US officials and courts to block extradition to Japan, where they will be tried on charges that they smuggled Ghosn out of the country in 2019 while the former auto titan was awaiting trial on financial misconduct charges. The Massachusetts men, held at a suburban Boston jail since their arrest in May, were handed over early on Monday, said one of their attorneys, Paul Kelly. Their lawyers had argued the accusations do not fit the law Japan wants to try them under and that they will be treated unfairly and subjected to “mental and physical torture”. They have accused Japan of pursuing the pair in an attempt to save face after the embarrassment of Ghosn’s escape. Michael Taylor, a US army special forces veteran in the past hired to rescue abducted children, has never denied the allegations. He gave an interview to Vanity Fair last year in which he described the mission in detail. When asked why he did it, he responded with the motto of the special forces: “De oppresso liber” or “to liberate the oppressed”. He refused to discuss the details of the case in an interview last month because of the possibility he would be tried in Japan. But he insisted that his son was not involved and was not even in Japan when Ghosn left. Ghosn, who became one of the auto industry’s most powerful executives by engineering a turnaround at the Japanese manufacturer, had been out on bail after his November 2018 arrest on charges that he underreported his future income and committed a breach of trust by diverting Nissan money for his personal gain. Ghosn has denied the allegations and has said he fled to avoid “political persecution”. Prosecutors have described one of the most “brazen and well-orchestrated escape acts in recent history”. Authorities say the Taylors were paid at least $1.3m. On the day of the escape, Michael Taylor flew into Osaka on a chartered jet with another man, George-Antoine Zayek, carrying two large black boxes and pretending to be musicians with audio equipment, authorities said. Ghosn, free on bail, headed to the Grand Hyatt in Tokyo and met Peter Taylor, authorities say. The elder Taylor and Zayek met the two others at the Grand Hyatt and shortly after split up. Peter Taylor took a flight to China while the others got on a bullet train and went back to another hotel near the airport, where Taylor and Zayek had booked a room. They all went in; only Ghosn’s rescuers were seen walking out. Authorities say Ghosn was inside one of the big black boxes. At the airport, the boxes passed through a security checkpoint and were loaded on to a private jet headed for Turkey, officials said. The Taylors had hired lawyers connected to Donald Trump, including the ex-White House attorney Ty Cobb, in an attempt to get Trump to block the extradition before he left office. In his interview with the AP, Michael Taylor implored Joe Biden to step in and said he felt betrayed that the US would try to turn him over to Japan. But the Biden administration declined to block the extradition. Under Trump, the state department agreed in October to hand the men over to Japan. But a federal judge in Boston put their extradition on hold shortly after their lawyers filed an emergency petition. The judge rejected their petition in January and the Boston-based first circuit court of appeals later denied their bid to put the extradition on hold while they appeal against that ruling. The supreme court justice Stephen Breyer last month denied a bid for more time for an appeal, clearing the way for the men to be handed over to Japan.