The home supporters were protesting against the club ownership of Dai Yongge and the match was halted after 16 minutes of play, with around 40 of the fans still refusing to leave the pitch some 68 minutes later.

The game had been interrupted shortly after kick-off when sections of the home fans threw tennis balls onto the playing surface at the Select Car Leasing Stadium.

Referee Ross Joyce took the players into the dressing rooms, while the supporters milled around the pitch, some letting off blue flares. Fans chanted anti-Dai slogans and unveiled a banner in the centre circle that read "football has an ownership problem".

After approaching the Vale fans, some of whom applauded them, most of the home fans started to head back to the stands. But many of them then returned and staged a sit-in in the centre circle.

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A statement posted on Reading's X, formerly Twitter, account, read: "We are fully aware of and understand our supporters' frustrations, but we must reiterate to our supporters that entering or throwing items onto the pitch can put the fixture at risk of abandonment and can result in personal consequences including banning orders."

With around 300 Reading fans remaining on the pitch, the game continued to be held up and at 3.56pm, officials from both clubs were in contact with the EFL fixtures management team to discuss "the best course of action".

Then, at around 4.25pm, the announcement for the match to be postponed was made. The fixture will be restaged later in the season on a midweek date.

Sell Before We Dai, a group calling for a change of ownership at Reading, said "the first fan-led match abandonment in our 152-year history should not be celebrated, but the spontaneous, unfiltered passion, as well as the will and determination of our fans, should be".

It added in a statement: "We understand that we will be punished by the EFL, but what we really need is help. Today was an outpouring of emotion from a fanbase not known for its hostility. We are scared for the future of our football club and the threat could not be more real.

"We want this to be our last abandoned match, but it is just the start of this elevated protest action."

Why are Reading fans unhappy with Dai?

Reading owner Dai is blamed by many supporters for the club's problems, including wages not being paid and a winding-up order being served in October over unpaid taxes.

Dai took charge in 2017 but has come under fire after the club was hit with a number of penalties for financial mismanagement, including a four-point deduction this season for a late payment of the monthly wage bill.

Former Premier League team Reading, who were relegated after 10 years in the Championship in 2023, have been deducted 16 points in under two years.

This season, they have received four points in deductions - a punishment that has seen them struggle in the League One relegation zone.

Selles fears Reading may have to play with empty stands

Reading manager Ruben Selles fears that the club may be forced to play home games behind closed doors "maybe for the rest of the season" following the abandonment.

"We know that there could be repercussions," he said. "A points deduction is unlikely, but it can happen. It could be that we play with an empty stadium for one or two games or even the rest of the season.

"There could be a financial punishment, of course. It's a big variety of things and it will be up to a panel of experts to decide."

Selles added: "We knew that something was going on (the planned on-pitch protest) from reading the social media and all its comments. I had a decision to make. The decision was to come here to compete and don't get distracted by those things.

"The invasion was not aggressive, it was passive. It was just to make the point. I'm sympathetic with the fact that we all want the best for Reading football club.

"I think our fans are proud with what the team is doing, the way in which we are playing and competing. But the fans are getting frustrated about the similar things that we are.

"I'm sympathetic but, really, what I want is just to play football matches and win football matches."

Port Vale manager Andy Crosby was not available for comment on the abandonment afterwards.

But the club later posted on X: "We'd like to thank our supporters for making the trip to Berkshire and wish you a safe trip back."

It was the second League One match to be abandoned on Saturday after Bolton Wanderers' home game against Cheltenham Town was called off after a medical emergency in the crowd.