Militants of the Islamic State group and al Qaeda could carry out joint attacks in India, the director general of the country’s National Security Guard, or NSG, said on Thursday, according to media reports. The statement by the head of the country's counterterrorism force comes just over a month after al Qaeda announced the creation of a South Asia wing to “raise the flag of jihad” across the Indian subcontinent.

“Now that they (al Qaeda) have declared an intention to attack India, they might combine with outfits like Lashkar-e-Taiba, ISIS and Indian Mujahideen,” NSG Director-General Jayant Choudhury reportedly said, adding that the Indian cities of Goa, Bangalore and Amritsar could be targeted by the militant groups.

“Terrorism has become more grim, what happened in Mumbai on 26/11 was a curtain raiser,” Choudhury reportedly said, referring to attacks carried out by militants of Lashkar-e-Taiba -- a Pakistani militant group -- in the Indian city of Mumbai in 2008. More than 160 people were killed and over 300 were reportedly injured in the attacks.

Earlier on Thursday, an Indian army commander in the conflict-ridden Indian state of Jammu and Kashmir also raised concerns over the possibility of attacks by the Islamic State group in India after masked men were seen waving flags of the militant group during Eid celebrations last week.

“The emergence of the ISIS flags merits concern and deserves the highest attention of the security agencies to prevent the youth of Kashmir from getting lured by ISIS,” Lieutenant General Subrata Saha said, according to the Press Trust of India, an Indian news agency.