Siraj, also a former BNP vice-chairman, breathed his last around 3:25 at Evercare Hospital in the capital, said BNP chairperson’s media wing member Sayrul Kabir Khan.

He said the BNP leader had long been suffering from cancer, and he was admitted to the Evercare Hospital on Monday as his condition worsened.

Alongside cancer,  Sayrul said Siraj had also long been suffering from diabetes, kidney failures and high blood pressure

He is survived by wife, one son, one daughter and a host of relatives to mourn his death.

From the hospital, his body was taken to his Gulshan residence in the evening through a mobile mortuary ambulance.

His body will be taken to Tangail on Wednesday where his separate namaz-e-janazas will be held at Elenga and Kalihati.

His body will be taken back to the capital and buried at Banani Graveyard after his final janaza at Gulshan Society Jam-e-mosque after Isha prayers.

Born in Kalihati of Tangail on March 1, 1943, Siraj was one of the organisers of the country’s Liberation War and a commander of the Bangladesh Liberation Force.

As an active student leader, he took part in the 1969 Mass  Upsurge Movement.

Siraj became general secretary of the undivided Chhatra League for 1970-72 period and played a key role in the Liberation War.

On March 3, 1971, he read out the manifesto of Bangladesh’s independence.

After the Liberation War, Siraj played an important role in the formation of Jatiya Samajtantrik Dal (JSD) quitting Chhatra League.

He joined BNP in 1995, and later he was made Minister for Forests and Environment in Khaleda Zia's cabinet formed in 2001.

Siraj was elected MP thrice--1979, 1986 and 1988--with JSD ticket from Kalihati and twice--1(5th February) 1996 and 2001.

As the environment minister, he earned reputation with is some bold initiatives, including banning polythene and removing two-stroke autorickshaw from Dhaka’s street, but some graft allegations were also raised against him.

He was arrested during the army-led caretaker government after 1/11 political changeover. Later, he was convicted in a graft case.

Though he was freed on bail, Siraj became inactive in politics since 2012 after he had been diagnosed with lung cancer. Later, he was diagnosed with   brain cancer.

Meanwhile, President Abdul Hamid expressed deep shock at his death.

Gono Forum President Dr Kamal Hossain, BNP acting chairman Tarique Rahman, secretary general Mirza Fakhrul Islam Alamgir and JSD president ASM Abdur Rob also condoled his death.