( CNN ) -- Two Burmese migrants accused of the brutal murder of two British tourists on a popular tourist island in Thailand last month have retracted their confessions , a lawyer representing them says . Zaw Lin and Win Zaw Htun , who have been in custody since October 1 , had admitted to killing David Miller and raping and murdering Hannah Witheridge on Koh Tao , according to Thai police . However the men now say they did so under duress after being physically abused by police , Surapong Kongchantuk , the head of the Lawyers Council of Thailand , which is acting for the two suspects , told CNN Wednesday . Surapong said the men deny the murder and rape charges , and that an official complaint to the justice department of Samui , which has jurisdiction over the island , has been filed . They appealed for fair treatment for the two accused , he added . Thai police could not be immediately reached for a response . The two Britons were found dead on a beach on the island , a popular tourist destination , on September 15 . Both were partially undressed with severe injuries to their heads . A hoe with blood on it was found close by , police said . Police Commissioner Gen. Somyot Poompanmuang previously told CNN that DNA in semen taken from Witheridge matched samples taken from the two men . `` The DNA matching result is out already and they matched with DNA found on the female victim , '' he said . Torture claims denied . Reports that the police extracted confessions through torture first surfaced earlier this month , when Burmese media reported that its two nationals had complained to a visiting lawyer attached to the Myanmar embassy . The revelation prompted national police chief Somyot Poompanmuang to hold a press conference in Bangkok to deny allegations his officers had tortured the suspects . Nevertheless , Amnesty International has called for a full , independent investigation into reports of misconduct by police officers . Allegations of torture should be investigated independently , and not by the Thai police , Richard Bennett , Amnesty 's Asia-Pacific Program director , told CNN earlier this month . He also said there were questions of due process that had arisen , specifically the absence of legal counsel prior to the confession , and difficulties with interpretation . `` There is a fairly long-standing record of ill-treatment , '' in Thailand , he said . `` Impunity is also a problem . If the investigation shows ill-treatment , those responsible should pay . '' The fact that the suspects are migrant workers , many of whom work in Thailand illegally , makes them more vulnerable , he added . Journalist Kiki D in Bangkok contributed to this report .
Burmese migrants who had previously confessed to double murder retract confessions . Lawyer acting for the two of his clients claim they were physically abused by police . Police had held a press conference the previous day to discuss torturing suspect . Amnesty International protests arrests , calls for independent investigation .