Glasgow, United Kingdom - "Harassed". "Victimised". "Criminalised". These are the words used by Scottish football supporters to describe their recent treatment at the hands of police.
On Saturday March 16, more than 200 officers - supported by mounted police and dog teams - took part in an operation to control what they described as an "illegal procession" by supporters of Celtic FC.
As a police helicopter circled overhead, the police lashed out with batons to control a crowd of around 150 fans.
Jeanette Findlay, chair of the Celtic Trust, said that she took a phonecall just after 1:00pm, and rushed to the scene in Glasgow's Gallowgate, an area of the city where fans often congregate before matches.
"By the time I got there, the Public Order Act had been read and there was a large group of mainly young people being kettled," she told Al Jazeera.
"I was absolutely shocked at the number of police officers that were there. I have not seen anything like it since the miners' strike. That is what it reminded me of."
- Jeanette Findlay, The Celtic Trust
"I was absolutely shocked at the number of police officers that were there. I have not seen anything like that since the miners' strike. That is what it reminded me of. Turning around 360 degrees, I counted 15 support vehicles."
The march was organised by the Green Brigade, an ultras group known for their colourful banners and constant singing in the stadium. They made headlines last year with a display of solidarity for Palestinian hunger strikers.
Speaking on condition of anonymity, a member of the Green Brigade told Al Jazeera they planned to walk peacefully up to Celtic Park in a show of solidarity with members who had been banned from matches.
He described the police as "out of control", saying that officers were "heavy handed" at best and "thuggish" at worst.
"Footage has already surfaced of people as young as 14 being manhandled by officers," he said. "Complaints have been made regarding a young girl who was struck by a policeman and there have been countless accusations of police misconduct made on [internet] forums by people who were in attendance."
A police spokeswoman dismissed these allegations as completely inaccurate. She said in a statement:
"Having reviewed the footage, senior officers are entirely satisfied that the officers on the ground dealt with the situation in a professional and proportionate way. Indeed, officers showed great restraint given the level of aggression and abuse they received."
Some 13 people were arrested on charges which included allegations of breaching the peace, assaulting a police officer and resisting arrest.
Home and away
Last week's violent confrontation is the latest and most high profile incident in what fans claim is an ongoing campaign of harassment and intimidation against them.
One member of the Green Brigade described how he had been stopped and harassed at matches - both at home and abroad.
"I've been threatened with arrest for having the temerity to take a photograph of a police officer, and once for having a scarf above my face [while watching Celtic play away at Aberdeen in freezing temperatures in January]."
He added: "The police film the section where I sit at Celtic Park at every single game, which I believe to be both intrusive and unwarranted."
The policing of football fans in Scotland has become much more intense since the Offensive Behaviour at Football Act came into force in March 2012 - creating a new criminal offence of "offensive behaviour at regulated football matches".
It was introduced after a bad tempered Celtic-Rangers match led to a media frenzy and a bout of national navel gazing about sectarianism in the sport.
Strathclyde Police has set up a dedicated unit, known as the Football Co-ordination Unit for Scotland, with specially trained officers and a two-year budget of almost £2 million ($3 million) to enforce the new law.
Supporters claim that the unit's activities go well beyond policing at football matches, with some alleging that their phones have been tapped and emails intercepted. Members of the Green Brigade say they have been harassed at their homes, at their places of work and at airports as they return from holiday.
Fans have been taken to court over a number of issues, ranging from singing to the displaying of banners and alleged breaches of the peace.
Al Jazeera put these accusations to Strathclyde Police. They say that, so far as they are aware, only one person has been arrested at Glasgow Airport on a football-related matter, and people who have been recognised at football matches are not being routinely stopped for questioning at airports.
The spokeswoman would not be drawn on claims that police were tapping fans' phones or monitoring emails, saying only that "we do not comment on intelligence matters".
"Celtic fans are being targeted, harassed, victimised and criminalised - and there is real anger at the way the police are going about this."
- Michael McMahon, Labour MSP
Labour's Michael McMahon, a member of the Scottish parliament, met with supporters groups at the Celtic Social Club this week. He said he believes that the legislation is a mess - and its enforcement is actually increasing tension.
"Celtic fans are being targeted, harassed, victimised and criminalised - and there is real anger at the way the police are going about this," he said.
A game of two halves
It is not just Celtic fans that are angry. The blue half of Glasgow, which follows Rangers, believes that they have also become a target for harassment.
Al Jazeera spoke to Ross, a member of Rangers ultras group, the Union Bears, who did not want us to use his last name.
"Supporters, especially Union Bears, are filmed by police using handheld video cameras during matches - home and away," he said.
At a recent away game against Annan Athletic, Rangers supporters arriving by train were met by the police at the station. They were only allowed to leave after they had shown ID or given their name and address to officers, and submit to being photographed.
Police say they were acting on intelligence that some fans intended to cause trouble, though fans describe the experience as intimidating.
"On a regular basis, it is common for a police officer to approach a member of our group and greet him by his name, asking him if he still works or lives at such and such."
- Ross, Union Bears
"On a regular basis, it is common for a police officer to approach a member of our group and greet him by his name, asking him if he still works or lives at such and such," said Ross of the Bears.
A Scottish government spokesperson told Al Jazeera: "This is an operational matter for the police, who are responsible for security in and around football matches. An 87 percent charge rate and 83 percent conviction rate for people arrested under the legislation shows that it's working well."
It is indisputable that Scottish football has provided a focus for religious sectarianism and, specifically, anti-Catholic prejudice.
Whilst Rangers supporters took pride in their Protestant heritage and strong connections to Ulster Unionism, Celtic's success gave hope to the city's Irish immigrants.
However, bigotry isn't just a 90-minute problem that ends when the referee blows the whistle. Until relatively recently, workplace discrimination was endemic in industries including engineering and shipbuilding.
"We've said all along that sectarianism goes well beyond football and Facebook," Dave Scott, campaign director for anti-sectarianism charity Nil by Mouth told Al Jazeera.
"There is a lot of confusion amongst fans, police - and even judges - as to what is, or is not, a breach of the act. We hope the forthcoming evaluation of the act will focus minds on this problem."
The Scottish Government is set to spend £150,000 ($226,000) to assess the impact of the Offensive Behaviour at Football Act.
In some ways, the confrontation between supporters and the state is a battle for the soul of the game. Modern football is increasingly focused on corporate power and the drive to make money out of fans' love for the beautiful game.
Glasgow City Councillor George Ryan concluded simply: "A war is being waged against young working class football supporters."
Follow Andrew McFadyen on Twitter: @apmcfadyen