Ending days of speculations, the authorities have at last executed the death row convict Jamaat-e-Islami leader Muhammad Kamaruzzaman for his crimes against humanity during 1971 Independence War.

The Jamaat leader was hanged from the noose at 10:30pm on Saturday, confirmed IG Prison Brigadier General Syed Iftekhar Uddin.

After an hour of the execution, two ambulances, guarded by security forces, came out of the jail gate with one of them carrying the body of Kamaruzzaman. There were also vehicles carrying journalists.

The motorcade has headed to Sherpur where the Jamaat leader will be buried at his village home.

He is supposed be buried at at Kumri Mudipara in Sherpur where he had collaborated with the Pakistani occupation forces by perpetrating war crimes during the independence war.

Kamaruzzaman is the second Jamaat-e-Islami leader to be executed for war crimes after Quader Mollah who had been executed on 12 December 2013 by the International Crimes Tribunal.

Earlier necessary preparations were made to execute him with high government officials concerned present there. 

Senior jail superintendent Farman Ali and deputy jail superintendent Lavlu received the executive order at about 2:41pm and the order was read out to Kamaruzzaman. 

Twenty-one members of his family went to the jail by three microbuses at about 4:10pm.

The prison authorities on Saturday asked Kamaruzzaman’s family to meet him at the jail.  The authorities on Saturday moved to hang a top Jamaat leader for overseeing a massacre during the nation's 1971 independence war, after he refused to seek clemency from the president.

Kamaruzzaman, the third most senior figure in the Jamaat-e-Islami party, was originally expected to be hanged in the early hours of Saturday morning, but the execution was postponed at the last minute.

No official reason was given for the delay, but junior home minister Asaduzzaman Khan told reporters the 62-year-old was now set to be hanged in the capital's main jail on Saturday.

‘The hanging of Kamaruzzaman... will take place today (Saturday),’ the state minister said.

On Friday, security was stepped up outside the jail where Kamaruzzaman was being held, police said.

Two magistrates visited him in prison to find out whether he would seek clemency from President Abdul Hamid, but the pair made no comment following the visit.

The move to execute him comes after the country's highest court rejected Kamaruzzaman's final legal appeal on Monday, upholding the original death sentence handed down to him by a controversial domestic war crimes court in May 2013.

Kamaruzzaman was convicted of abduction, torture and mass murder including a slaughter in a remote northern hamlet that has since become known as the ‘Village of Widows’.

The conviction confirmed allegations that Kamaruzzaman was one of the chief organisers of a pro-Pakistan militia that killed thousands of people.

The conflict led to the creation of an independent Bangladesh from what was then East Pakistan.

If the execution is carried out, Kamaruzzaman would become the second Islamist so far hanged for war crimes, though several others have been handed death sentences.

The UN on Wednesday urged Bangladesh against carrying out the sentence, saying his trial did not meet ‘fair international’ standards.