A Bangladesh military captain arrested after nearly 25 years on the run over the assassination of the country's founding leader will be executed, officials said Wednesday. 

Sheikh Mujibur Rahman, the father of current Prime Minister Sheikh Hasina, was killed along with most of his family in a military coup on August 15, 1975, nearly four years after he led Bangladesh to independence from Pakistan.

In 1998 Abdul Majed was sentenced to death along with a dozen other army officers over the murders. 

Bangladesh's Supreme Court upheld the verdict in 2009 and five of the killers were executed several months later.

Majed is believed to have fled to India in 1996. He returned to Bangladesh last month, a prosecutor told reporters. 

Acting on a tip-off, counter-terrorism police arrested Majed on Tuesday as he rode in a rickshaw in the capital Dhaka, said police inspector Johurul Haque. 

"The formalities to execute him have already begun," Justice Minister Anisul Huq told AFP, adding that the former officer will not be able to appeal his sentence.

Huq said Majed's only option to avoid the gallows was to appeal to the president for clemency. 

However, since President Abdul Hamid is a close confidante of Hasina, any mercy appeal is expected to be turned down, paving the way for his execution within weeks. 

Hasina, whose public celebrations this year for the centenary of her father's birth have been hampered by the coronavirus pandemic, survived the 1975 attack because she was in Europe with her sister.

In a video message, the country's home minister called Majed's arrest "the best gift of Mujib centenary year".

The road to getting justice for the 1975 assassination was long, and the killing continues to poison Bangladesh's murky political scene to this day.

Successive post-coup military governments rewarded the killers with diplomatic positions and several of them were even allowed to form a political party and contest polls in the 1980s.

For 21 years, an indemnity law enacted by the post-coup government prevented prosecution of the killers. This was only overturned after Hasina came to power in 1996.

Hasina has also long accused Ziaur Rahman, president from 1977 until his assassination in 1981, of orchestrating her father's murder.

This is denied by his widow Khaleda Zia, prime minister from 1991-1996 and 2001-6 and Hasina's former ally turned arch enemy who was convicted of graft in 2018, charges she said were fabricated.