BELGRADE: Serbia’s foreign minister said Wednesday an incident in which a pro-Albanian flag flown by drone sparked violence on and off the pitch at a football match against Albania was a “political provocation.”

The Euro 2016 qualifier between the Balkan rivals had to be abandoned on Tuesday after a banner showing claims for a “Greater Albania” was flown low over the Partizan Stadium in Belgrade.

The flag was pulled down by Serbian player Stefan Mitrovic, triggering a brawl between the two teams.

Some of the 20,000 Serbian supporters ran on to the pitch and attempted to kick and punch the Albanian players until the referee ordered the teams to leave the field as smoke flares and other missiles rained down from the stands.

Riot police eventually moved in to restore calm.

Albanian fans had been banned from attending the match.

The violence could endanger a planned historic visit to Serbia by Albania’s Prime Minister Edi Rama and risks inflaming fresh ethnic tensions in the Balkans.

The European Commission said it was “disappointed” by the violence and praised Belgrade’s “professionalism” in dealing with the situation.

Serbian Foreign Minister Ivica Dacic described the incident as a carefully planned “provocation” and blamed Edi Rama’s brother Olsi for orchestrating the stunt.

“What is particularly disturbing is that it is the work of the brother of the Albanian prime minister, who is about to be hosted by Belgrade,” Dacic said.

Olsi Rama denied the claims.

Serbian President Tomislav Nikolic warned of the “clear intentions” of those responsible to “provoke unrest in in Serbia and to try to destabilize the whole region.”

The Serbian Football Federation said the incident was “an offense not only for citizens of Serbia, but also of Greece, Macedonia and Montenegro” — the countries that would be part of a “Greater Albania.” Next Wednesday’s visit to Belgrade would be the first by an Albanian prime minister for 68 years.