Afzal Guru, a one-time fruit merchant, was executed Saturday over his role in a deadly attack on the Parliament in 2001.
Guru was hanged at New Delhi's Tihar Jail after President Pranab Mukherjee rejected a mercy appeal. He was only the second person to be executed in India in nearly a decade.
Here are the reactions to his execution:
BJP welcomed the execution of Parliament attack convict Mohammed Afzal Guru, saying it was a "much awaited and much wanted decision".
The Oppostion party questioned the delay in the execution saying it should have happened much earlier after the confirmation of the capital punishment by the Supreme Court in 2005.
"Why this sort of delay inspite of overpowering desire of the people of the country that those who are accused of such a heinous offence ought to be given the capital punishment as affirmed by the highest court of the land. This question would remain important and an answer would have to be found out," BJP chief spokesperson Ravi Shankar Prasad told reporters.
Party vice-president Mukhtar Abbas Naqvi said Guru was a conspirator in waging war against the nation and responsible for attack on the temple of democracy (Parliament) in India.
"It is a late decision but in national interest. There was a strong anger across the nation due to the delay (in execution). Despite the late action, people in the country have heaved a sigh of relief and this hanging has given a message to the terrorists and the anti-national forces working against the country," the BJP leader said.
His colleague Rajiv Pratap Rudy welcomed the execution saying it was a "much awaited and much wanted decision".
"This action is delayed. But undoubtedly it is a welcome action" so that the world could see that India is committed against terror and the fight against terror, he said.
Congress said that a message of "zero tolerance" against terrorism has been sent through Guru's execution.
Party spokesman Rashid Alvi said "we have sent the message to the world that we cannot tolerate terrorism at any cost. If anybody tries to commit (any act of terror), he will be punished. People of our country and government have zero tolerance against terrorism," he said.
Hitting out at the opposition NDA, he said those who were released in Kandahar (Air India plane hijack) eventually made the conspiracy to attack Parliament.
Another party spokesman Sandeep Dikshit said "Law has taken its course. Justice has been done".
His party colleague Abhishek Singhvi said the decision to hang Guru "vindicates Congress stand that it is culmination of constitutional and legal process."
"We have never played divisive politics on this issue as BJP has done. We have not, as BJP does, tried to make executions a barometer of our patriotism or jingoism," he said.
"As to critics regarding why it (the execution) was carried out before Budget session of Parliament, such irresponsible and childish opposition deserves no response," he added.
Jammu and Kashmir CM Omar Abdullah:
Abdullah said he was told about Afzal Guru's imminent hanging the previous evening and told "to take steps to control the situation" in the state.
"We were informed to take steps to control the situation in (Jammu and Kashmir)," Abdullah said.
"In contrast to (JKLF chairman) Maqbool Bhat, there was no case against Afzal Guru in the state and as such the chief minister or the government did not have to sign his ... death warrant," Abdullah said.
"Curfew has been imposed as a preventive measure. The army has not been called out anywhere. The police and the CRPF are maintaining law and order," he said.
The chief minister appealed to stay calm and control their emotions.
"There are some elements among us who would try to vitiate the prevailing peace in the Kashmir Valley using the development."
Moderate Hurriyat Conference led by Mirwaiz Umar Farooq announced four-day mourning after Afzal guru was hanged.
"We call on people to observe four-day mourning on the hanging of Guru. A complete shutdown will be observed over the mourning period," Shahidul Islam, spokesman of the amalgam, said.
Chairman of All Parties Hurriyat Conference (APHC), Syed Ali Shah Geelani, condemned Guru's hanging, saying the latter was not involved in the 2001 Parliament attack and was also not given a chance to defend himself in connection with this case.
"After Maqbool Bhat (Kashmiri nationalist) sahab was hanged in the same manner on February 11, 1984 in Tihar Jail, it is a second big blow for the people of Jammu and Kashmir. We declare it as injustice because our stand on Afzal Guru sahab is that he was not involved in the Parliament attack. Personally, he was not involved in the attack. He was not given the chance to defend himself in the trial court," said Geelani.
"On the basis of that, I can say that the punishment given to him is injustice and I condemn this. Even his wife, son and relatives were not informed about the execution. His family members should have been given a chance to meet him prior to the execution," he added.
Meanwhile, Hilal Ahmad War of the hardline faction of the All Parties Hurriyat Conference (APHC), criticised the hanging of Afzal Guru, and warned of revengeful action.
"We will give a response to this to India. We will take the revenge. We condemn this action of India. India wants war. This is a provocation. We will call for a strike and will respond to India on this. The situation will go back to that of 90's, and the condition of Kashmir will be spoilt," he said.
CPI(M) said that the law of the land has taken its course in the 2001 Parliament attack case.
"I think, the law of the land with all its provisions has finally been completed as far as the Afzal Guru case and the attack on the Indian Parliament is concerned," CPI(M) politburo member Sitaram Yechury said.
Kashmir Opposition Peoples Democratic Party (PDP) expressed disappointment and appealed to the people of Kashmir to exercise restraint.
"PDP is disappointed at the hanging of Afzal Guru. We had urged that political sensitivities should be taken into considering while taking a decision on his clemency plea," PDP spokesman Nayeem Akhtar said.
"We appeal to the people of Kashmir to exercise restrain and not allow repeat of 2010 situation when more than 100 youth were killed," he said.
Delhi University lecturer SAR Geelani who was arrested for being involved in the Dec 13, 2001 attack on Parliament said that Afzal Guru's family was not told about his hanging.
"Protocol was not followed. Even now the family has not been informed," Geelani said.
Geelani was acquitted by the Supreme Court in October 2003.
Criticising the government, he said: "They have thrown everything to the winds. The whole thing is politically motivated. It is because of votebank politics. The government is playing to the galleries."