Bulgarian prime minister calls on the country's FA president to quit following the racism from fans against England

England's black players and backroom staff were subjected to abuse at various stages of the match, but the game was ultimately completed with England winning 6-0 in Sofia.

Sanctions from European football's governing body UEFA seem sure to follow, and Bulgarian leader Boyko Borissov is now reported to have told the president of the Bulgarian Football Union, Borislav Mihaylov, to stand down.

"The prime minister called me urgently a short time ago," Bulgarian sports minister Krasen Kralev said in quotes reported by sportal.bg.

"The government has done a lot for the development of Bulgarian football in the last four years.

"But after the recent events, having in mind the whole state of football and last night's incidents, the prime minister has ordered me from today to suspend any relations with the BFU, including financial ones, until the resignation of Borislav Mihaylov."

Borissov later posted on Twitter about what had happened on Monday night.

"I strongly condemn the conduct of some of the fans at the stadium #BULENG," he wrote on the social media site.

"It is unacceptable that Bulgaria, which is one of the most tolerant states in the world and where people of different ethnic and religious background peacefully live together, should be associated with racism."

The governmental interference in the Bulgarian association is likely to attract the interest of football's world governing body FIFA, and could result in further sanctions in addition to anything that may come from UEFA.

Mihaylov wrote to UEFA before Monday night's match criticising the fact that England players had spoken about the potential for racist abuse during the fixture, calling it an "unjust branding" of Bulgarian supporters and urging UEFA to impose sanctions if England did not follow protocol.

Piara Powar, the executive director of the Fare network which had spotters inside the Levski Stadium on Monday night, said he believed some of the racism was motivated by a desire to create a problem for Mihaylov by certain supporters.

"They were getting involved in racism because they are racist, but also because they do not respect the leadership of the FA president," he told the PA news agency.

"So when the FA president was telling them not to be racist before the match, it was almost a signal for them to contradict him and punish his leadership of the FA."

UEFA is set to receive the report of the match referee and match delegate on Tuesday, and it will then be for its control, ethics and disciplinary body to open an investigation.

What happens next?

What evidence will UEFA look at?

UEFA's control, ethics and disciplinary body will consider the reports from the match referee, its match delegate and from 'spotters' in the crowd working for the Fare network, which works to stamp out discrimination and promote inclusion in the European game. It will also look at evidence from other sources, such as television footage and CCTV. Football Association chairman Greg Clarke said on Monday night that security staff from his organisation would gather witness statements, and UEFA would also look at these if submitted.

What happens then?

The UEFA control, ethics and disciplinary body must decide whether to open an investigation based on the evidence presented to it. The body may wait until after the final group of Euro 2020 qualifiers of this international break is played on Tuesday night to look at evidence, but may move faster than that.

What punishment could Bulgaria face?

Under Article 14 of UEFA's disciplinary regulations which relate to racism, the punishment may be to order the Bulgarian Football Union to play one match behind closed doors and issue a 50,000 euros fine (which equates to just over £43,500). However, there is provision under Article 14, 'where circumstances of the case require it' to impose additional disciplinary measures such as ground closure for multiple matches, forfeiture of a match, points deduction or disqualification from the competition.

What sort of punishments have been issued in the past?

The three-step UEFA anti-racism protocols were launched in a resolution at UEFA Congress in London in 2013. No game has yet been abandoned under the protocol. No team at club or national team level has yet had points deducted or been disqualified over an offence of racism. One of the most severe punishments to date was the decision in July 2015 to impose a two-match stadium closure on the Croatian federation. That sanction was imposed because a Nazi swastika had been burned onto the pitch before a match against Italy in Split, which was already being played behind closed doors because of a previous offence. The Montenegrin association was ordered to play a match behind closed doors and fined 20,000 euros after its supporters were found guilty of racially abusing England players during a qualifier in March. Tottenham defender Danny Rose said he was "lost for words" at the leniency of the sanction and added: "It's a bit shocking but there's not much I can do now. I just hope I don't ever have to play there again and we just have to move on now." Players have faced more stiff punishments for racism-related offences - in August Ukrainian goalkeeper Kostyantyn Makhnovskyi, who was playing for Latvian side Ventspils, was banned for 10 matches.

Will UEFA comment before a charge?

It is unlikely but the pressure will be on for UEFA president Aleksander Ceferin, or another senior figure within the organisation, to issue a statement of some kind.