Posing as journalists, the Shiv Sainiks entered the venue, which was filled with bona fide representatives of the media. Soon after the event started, the Sainiks shouted slogans and tore down banners put up in the venue, disrupting the conference and demanding that the Pakistani artistes return to their country.
This is hardly the first time that the Shiv Sena has disrupted events involving Pakistani artistes or performers. Last year, the Shiv Sena disrupted a Sindhi Sufi music festival in Delhi in which Pakistani artistes were performing. In 2010, it protested against Bigg Boss, a TV show, for allowing Pakistani television host Begum Nawazish Ali and actor Veena Malik to participate in it.
In 1999, the Sena dug up the cricket pitch at Delhi's Ferozeshah Kotla stadium to protest against the Pakistani cricket team playing in India.
Organisers of Tuesday's event had therefore expected trouble, and had asked that police be present at the venue, which is near a police station. The police rounded up the Shiv Sainiks and detained them, yet the press conference had to be cancelled because of the disruption.
Police said that they arrested 17 men and three women for disrupting the conference, and have filed a case of unauthorised entry against them.
"We condemn this act and the Shiv Sainiks' jingoism," said Gurbir Singh, president of the managing committee of Mumbai's Press Club.
Jatin Desai, the Press Club member who had organised the press conference, criticised the Sena for interfering in a cultural exchange between India and Pakistan, observing that the event had marred the otherwise cordial relations that the Mumbai Press Club enjoyed with the Karachi Press Club, with which it had conducted various exchange programmes. In any case, the Pakistani band had performed twice before at the Mumbai Press Club, with no protests from the Sena, he said.
Rahul Narvekar, a spokesman for the Shiv Sena, was unfazed by the criticism. "No Pakistani should be allowed to exploit Indian soil, whether it is for music or sports," he said.
But he added that the protest had not been planned. "It was a spontaneous reaction by the concerned public," he said.
The Shiv Sena will formally protest against the band and will not permit them to perform in Mumbai or anywhere in Maharashtra, he threatened, adding that such "spontaneous reactions" could be expected if the band tried to perform in Mumbai or elsewhere in the state.
"If the government had acted in time, there would have been no need for such disruption," he said, adding that the Sena would approach the government to deny the band permission to perform in the state.
Aroon Tikekar, senior journalist and author, regretted the Sena's persistent hooliganism. "It is sad that the Shiv Sena is not growing up," he said. "Ultimately, incidents like this spoil the image of Maharashtrians, outside the state and outside India."
But the Sena's insular brand of politics would not pay it any political dividends, said Surendra Jondhale, a political analyst and professor at Mumbai University.
The Sena would continue to indulge in such activity as it was its way of advancing its Hindutva agenda, he said, which made an Islamic country such as Pakistan a target, especially considering the history of conflict between the two nations.
"What happened on Tuesday is not new," he said. "But the Sena's chauvinistic brand of politics is wholly out of sync with the current political climate, given the emergence of the Aam Aadmi Party and the new political language that party is speaking."
The Shiv Sena was continuing such protests because it still thought that it pandered to the electorate by acting this way, he said. "But they are reading the situation wrong."
The Sena's chauvinism had always limited it to Maharashtra and prevented it from becoming a national party, but it would lose ground even in Maharashtra by indulging in acts such as creating trouble at the Press Club, he said.
"None of the Sena's leaders had the political acumen of a man like [former Prime Minister] AB Vajpayee, who put effort into the peace talks between India and Pakistan by inviting [former Pakistan] President Pervez Musharraf to Delhi to address the tensions between the two nations," he said.
And just as the Sena didn't take a cue from Vajpayee then, it was failing to read the signals sent out by AAP, whose anti-corruption agenda was already appropriated in part by the Congress and other parties.
"What the Sena is doing is of no use to itself or to Maharashtra. It's time it shifted its priorities, but it is unlikely it will," he said.