The nation observes the Jail Killing Day today with due solemnity commemorating the 1975 killing of four national leaders inside Dhaka Central Jail.On November 3, 1975, the four national leaders and heroes of the country`s Liberation War -- Syed Nazrul Islam, Tajuddin Ahmed, Captain Mansur Ali and AHM Quamruzzaman -- were assassinated inside the jail.The four leaders had played a key role in forming the Mujibnagar government in exile that led to the Liberation War of 1971 with Syed Nazrul Islam as the acting president, Tajuddin Ahmed as the prime minister, Mansur Ali as the finance minister and AHM Qamruzzaman as the home, relief and rehabilitation minister.President Abdul Hamid and Prime Minister Sheikh Hasina issued separate messages on the occasion.In his message, the President said, "The aim of the killers was to erase the ideal of Liberation War from the minds of the young generation apart from the rise of undemocratic autocratic rule."The Prime Minister said, "The killings of four national leaders were the continuation of the killing of the Father of the Nation with his family. Through it, the conspirators had wanted to destroy the spirit of the Liberation War by erasing the name of Awami League."Meanwhile, Awami League, its associate bodies and other political parties chalked out elaborate programmes to mark the day.The programmes include hoisting of national flag half-mast and party flags, placing wreaths at the portrait of Bangabandhu at Bangabandhu Bhaban at Dhanmondi, offering fateha at the Banani Graveyard and wearing black badges.Prime Minister Sheikh Hasina paid rich tributes to Father of the Nation Bangabandhu Sheikh Mujibur Rahman by placing wreaths at his portrait at 7am.Sheikh Hasina first placed a wreath as the Prime Minister at the portrait of Bangabadhu and stood there for some time in solemn silence as a mark of respect to the architect of independent Bangladesh.Later, flanked by central leaders of Awami League, Sheikh Hasina, also the AL chief, placed another wreath at the portrait of Bangabandhu.The ruling party organised a public rally at Suhrawardy Udyan on Monday marking the day where Prime Minister Sheikh Hasina spoke as the chief guest.Awami League general secretary and public administration minister Syed Ashraful Islam in a statement urged all to observe the day with due solemnity.