"Such language can only be spoken by a traitor. If some Indian leader says this, it is very unfortunate," party spokesman Sanjay Jha told reporters.
His remarks came a day after Modi said that three AKs have emerged as a unique strength for Pakistan.
"One is AK-47 which has been used to cause bloodshed in Kashmir. The second is A K Antony, who informs Parliament that people wearing the dress of Pak army beheaded our soldiers while our Army says Pakistanis had come. Who do you want to benefit with your statement...," he asked.
He was attacking Antony over his statement made in Parliament last year when Pakistani armymen had intruded into Mendhar sector in Jammu and Kashmir and killed two Indian soldiers, beheading one of them.
Posing questions to Modi, Jha asked whether leaders during the NDA rule were traitors when Kargil conflict took place after killing of 50 Indian soldiers and terrorists were released after the Kandahar plane hijack.
"Modi and BJP should answer to the nation," he said.
Making light of the BJP PM candidate's pitch for making him the "watchman" of the nation, he said, "People of India saw when riots took place in Gujarat in 2002. The watchman turned into a thief. It was NDA government at the Centre and politics of communalism happened in Gujarat".
Responding to questions on whether Congress feels that Rahul Gandhi should contest from Varanasi, Jha shot back saying, "Those who claim to have a 56-inch chest should come to Amethi if they have the guts."
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