New Delhi: The BJP on Tuesday launched a harsh attack on the Congress on the 49th anniversary of the Emergency, with Union Home Minister Amit Shah saying it is the biggest example of the opposition party's long history of killing democracy and repeatedly damaging it.

The president of the BJP, J. P. Nadda, stated in 'X' that those who today proclaim themselves guardians of Indian democracy have spared no effort to suppress the voices raised in defense of constitutional values.

Defense Minister Rajnath Singh said the emergency, imposed by then Prime Minister Indira Gandhi in 1975 before lifting it in 1977 and calling elections, is a dark chapter in Indian democracy that cannot be forgotten.

Dictatorship and abuse of power were on blatant display during the period, Singh said in 'X', adding that it raises a big question mark over the commitment to democracy of various political parties.

The BJP's harsh criticism of Congress came amid a coordinated campaign by opposition parties to portray the government led by Prime Minister Narendra Modi as going against the Constitution.

Congress and other opposition members brought copies of the Constitution to Parliament on Monday as the first session of the 18th Lok Sabha began.

Modi on Monday also invoked the imposition of emergency against the Congress and called on people to ensure that this is never repeated.

In his Hindi post on 'X', Shah said the "arrogant and autocratic" Congress government had suspended people's civil rights for 21 months in the name of one family's power.

Censorship was imposed on the media, the Constitution was amended and even the judiciary was limited, he said, paying tribute to those who fought against the Emergency.

BJP chief and Union Minister Nadda said the Congress's political decision to impose a state of emergency had shaken the very pillars of democracy by trying to trample on the Constitution given by B R Ambedkar.

"During this period, those who today claim to be guardians of Indian democracy made no effort to suppress the voices raised in defense of constitutional values," he said.

"I am proud that our Party belongs to that tradition that resisted the Emergency tooth and nail and worked to protect democracy," Nadda added.