Dhaka , Bangladesh ( CNN ) -- Bangladesh hanged an Islamist leader Thursday despite pleas not to from the United Nations . The execution came after the country 's Supreme Court upheld the death sentence against Abdul Quader Mollah , state-run news agency BSS reported . Mollah was sentenced in September after being convicted of crimes against humanity that date back to 1971 , during the country 's war for independence . The execution , originally scheduled for Tuesday , was delayed by the Supreme Court at the last minute . Mollah was the assistant secretary general for the Jamaat-e-Islami party , which earlier this year was banned from taking part in elections . Court decisions in his case , and others against senior Jamaat leaders have resulted in violent protests in the streets . In February , he was convicted of war crimes by an international panel set up by the government in an attempt to bring to justice those accused of atrocities . He was originally sentenced to life in prison , but many Bangladeshis held protests saying the sentence was n't harsh enough . The Supreme Court then sentenced him to death . In the country 's legal system , that decision can not be appealed . Concerns over trial . Two U.N. human rights experts called on Bangladesh on Monday to halt the execution because of concerns that Mollah did not receive a fair trial . `` The right of appeal is of particular importance in death penalty cases , '' said Gabriela Knaul , U.N. special rapporteur on the independence of judges and lawyers . `` Anyone convicted of a crime has the right to have his or her conviction and sentence reviewed by a higher tribunal , as laid down in the International Covenant on Civil and Political Rights to which Bangladesh is a party , '' she said in a statement . `` This provision is violated where a court of final instance imposes a harsher sentence that can not be reviewed , '' the statement said . Christof Heyns , U.N. special rapporteur on summary executions , said capital punishment `` may be imposed only following a trial that complied with fair trial and due process safeguards . ... Only full respect for stringent due process guarantees distinguishes capital punishment as possibly permitted under international law from a summary execution , which by definition violates human rights standards . '' On Tuesday , U.N. High Commissioner for Human Rights Navi Pillay called for a stay , saying the trial had not met stringent international standards for the death penalty , the U.N. said in a statement . The United Nations opposes the death penalty in any circumstance . Political tensions . Jamaat , a major ally of the main opposition party Bangladesh Nationalist Party ( BNP ) , is a constant thorn in the side of the ruling Awami League . Jaamat enjoys considerable support , particularly in rural areas . And periodically , it mobilizes its adherents in large-scale demonstrations in Dhaka to show its strength . But it has faced pressure from the Awami League and progressive groups that point to Jammat 's role during Bangladesh 's struggle for independence from Pakistan . Between 1 million and 3 million people were killed in the nine-month war . The International Crimes Tribunal , the court set up by the government in 2010 , has convicted several other top Jamaat leaders of crimes against humanity . Jamaat acknowledges that it opposed Bangladesh 's struggle for independence , but it has decried what it calls a smear campaign against it . It has also questioned why the Awami League is only now pressing forward on war crimes trials when it did n't do so while in power during the 1970s and 1990s .
NEW : Abdul Quader Mollah was hanged Thursday , state media reported . But the court postponed the execution shortly before it was to take place . After further hearings , it has now said the hanging can go ahead . U.N. officials have expressed concern about the standards of his trial .