By Ben Church, CNN

(CNN) -- With three flashpoints in as many days, Britain's football authorities are facing questions as to whether they are doing enough over the issue of player safety and their approach to hooliganism

On Sunday, a spectator was able to run onto the pitch and swing a punch at Aston Villa player Jack Grealish during a match in English football's second tier.

Later in the day a supporter was also able to run onto the pitch in the Premier League game between Arsenal and Manchester United.

Once again, the fan avoided stewards before shoving United defender Chris Smalling while celebrating his side's second goal in Arsenal's 2-0 win.

"Commenting would only add to the attention he craved," said Smalling on Twitter.

But it's not just English football that's had to deal with hooliganism in recent days. On Friday in Scotland, Rangers' player James Tavernier was confronted by a fan during the match against Hibernian.

'A serious problem'

All three men involved in the recent attacks have been arrested. Paul Mitchell, the Birmingham supporter who punched Grealish, has been sentenced to 14 weeks in prison after he pleaded guilty to a pitch invasion and common assault at Birmingham Magistrates Court Monday. He has also been given a 10-year ban from attending football matches.

Former Newcastle United and England international Alan Shearer says Birmingham should face strong sanctions and that the various organizations that regulate English football are facing a watershed moment.

"They [Birmingham] should have the strongest possible punishment," Shearer told BBC Sport.

"Someone is going to get hurt, either a player or an official, if they do not stamp this out now. They have to come down heavy."

The Arsenal fan who ran onto the pitch at the Emirates Stadium has been charged with common assault and entering the field of play by the Metropolitan Police.

British football has history when it comes to hooliganism. Fans of England's national team became particularly notorious for pre-match clashes with opposition supporters before the turn of the millennium.

Fast forward to June 2016 and a French court sentenced five English football fans to jail terms for their roles in the violence that marred the England-Russia match at the Euro 2016 tournament.

In the 1980s, English clubs were banned from playing European club competitions after the 1985 Heysel stadium tragedy when fighting fans at the European Cup final caused a crush that killed 39 supporters of Italian club Juventus.

In 1993, tennis player Monica Seles was stabbed on court and England women's manager Phil Neville suggested that could possibly happen in British football.

"We need to start protecting players properly," said Neville to BBC Sport.

"All it takes is for one of these people who get on the pitch to have a knife or other weapon and it will be a footballer who is badly hurt."

How exactly players can be better protected is up for debate, but former Birmingham player David Cotterill went as far as to say that armed police could be the answer.

"We need more security. I am not condoning guns at games but if the police are going to be armed, I think that is the way forward," Cotterill told BBC Wales.

'Strongest possible punishment'

Fears of what could happen next is also a talking point among professional players.

"Whether it's the FA, the Premier League, FIFA, something's got to be done maybe with extra stewarding or whatever," Manchester United captain Ashley Young told Sky Sports after the match.

"It's a concern with the one earlier [Jack Grealish] and the one with Chrissy [Smalling], something has definitely go to be done."

All the clubs involved in the above incidents have issued apologies to the affected players and promised to do more to stop such attacks in the future.

The Professional Footballers' Association (PFA), which represents football players in Britain, also called for appropriate punishments.

"Over the last few decades there has been a great improvement in match day security, however incidents like this demonstrate certain problems have not been eradicated and that players can be particularly vulnerable," a PFA statement read.

"We must address issues of violence and player safety -- this should include continued efforts with regards to education but be underpinned by strong punishments and sanctions."

Governing bodies respond

The English Premier League (EPL) said it would "work with all the relevant parties to address the issue of player and match officials safety on the pitch."

"In all circumstances the playing surface is for players, not supporters and those playing in the game must be able to do so safe in the knowledge they will not be subjected to this type of behavior," said an EFL spokesperson.

Meanwhile, the Scottish Professional Football League (SPFL) confirmed it would "review the specific circumstances of that event in conjunction with the match delegate and the police and take any appropriate steps."

The Football Association (FA), English football's governing body, released a statement condemning the weekend's incidents.

"This weekend a line has been crossed in terms of fan behaviour. On Sunday we saw two separate incidents, at Birmingham City and Arsenal, of individuals entering the field of play and assaulting players," said an FA spokesperson.

"Not only is it an offence to enter the pitch, which could result in a club ban and criminal charges for the individual, but it also puts the safety of the players at risk. This is entirely unacceptable and we strongly condemn both incidents.

"We will be working with the clubs, the leagues and the police to discuss what collectively needs to be done to protect players and officials on the pitch. In addition, we have written to both Birmingham City and Arsenal to seek their observations to examine the security measures they had in place."