Members of the internet hacking group Anonymous have been staging protests across 16 cities in India, against what they say is internet censorship in the country.
Mumbai's Azad Maidan sports ground is often packed with children playing cricket, but the bowlers and batsmen were joined on Saturday by a sea of Guy Fawkes masks.
The costumes are a hallmark of the internet "hacktivist" group Anonymous which organised a series of protests in Indian cities, including Mumbai.
"I'm here for internet freedom. There's restrictions on speaking online. That's why I'm here," says 19-year-old Amisha, a student who was one of around 100 protesters in Mumbai.
Holding banners calling for freedom from censorship, the group were protesting against India's internet laws.
"India is following China and Iran. They don't want the right information to reach people," said 20-year-old student Nishant, whose face was hidden behind a scarf and sunglasses.
"There are some sites they've blocked for information which is relevant to us. Information which is useful to us as citizens of this country," he added.
Speaking to the BBC via their internet chatroom, members of Anonymous India said they were representing the "common man" and were simply ordinary internet users trying to make a point.
Anonymous India organised its Occupy campaign against what it believes is the unfair blocking and banning of file sharing sites by Indian internet service providers (ISPs) such as Reliance Communications and Airtel.
"We are protesting arbitrary, extra-judicial censorship, where not even the government knows - or cares - who controls what," said @anamikanon from Anonymous on the group's chatroom.
Last month a number of Indian ISPs blocked access to sites that allow streaming of video content, such as Vimeo and Dailymotion, and a number of file-sharing sites, including Pirate Bay, following a court order which centred on the issue of internet copyright.
A Chennai-based film company, Copyrightlabs, called on big Indian ISPs, including Reliance Communications, MTNL and BSNL, to prevent access to websites which allowed users to illegally watch two of their Bollywood movies, Three and Dhammu.
The court order, known as an Ashok Kumar order, is like a John Doe order in the United States - designed to protect the copyright of music, films and other content.
The blocking of access to file-sharing and torrent websites prompted Anonymous India to hack into more than 15 sites, including the Indian Supreme Court, two political parties and the Indian telecoms providers.
The group carried out a number of "Denial of Service" (DDOS) attacks, which can temporarily suspend connection to a site.
It also claims it was able to enter the servers of Reliance Communications, and in a press conference in May, presented a list of the file sharing sites it alleges the ISP had restricted access to.
Reliance Communications refused to comment on claims they are restricting access to sites, but pointed the BBC to a statement from 26 May, in which the company said it had the "strongest possible IT security to tackle unwarranted intrusions," adding that their servers could not be hacked.
Anonymous says it is not supporting piracy, but that many file-sharing sites are used in a perfectly legitimate way, for example to share photos or software code.
"File sharing is the lifeline of the internet, that's why it came into being", said tomgeorge, also from Anonymous, via the chatroom.
The group is also protesting against Indian government IT regulations that came into effect last year, which force websites to remove objectionable posts within hours of receiving a complaint.
Some internet campaigners who agree with the view that the internet is too regulated in India do not agree with Anonymous's method of attacking websites.
"I can understand the need for them to take action - because frankly, one feels quite helpless right now, and there needs to be more awareness - but I'm against taking down websites," says Nikhil Pahwa, the editor of Medianama, a blog covering the digital industry in India.
"There are a number of organisations trying to help the government understand the negative impact of their rules, but when you start attacking government websites, it ends up having a negative impact too."
Mr Pahwa says he believes attacks on these sites are counter-productive because they inevitably encourage politicians to bring in stricter rules to prevent them happening, which defeats the object.
The government stands by its belief that sites do need to be regulated, so that offensive and blasphemous content is not posted. As for copyright, it maintains that court orders exist to protect film makers from piracy.
But members of Anonymous say they will continue their actions until restrictions are lifted.
"The government can't stop piracy in a country by just banning sites. This is a country where you have people selling pirated CDs on trains in streets... it is actually too much to expect," says Anon3x3Kalki, another member of the group.