Thousands rally in Macedonia amid unfolding political crisis (DRONE VIDEO)

Crowds of anti-government protesters have taken to the streets in the Balkan state of Macedonia, as unrest unfolds in the country over a wiretapping scandal, involving the country’s current leader, Nikola Gruevski.

Over 20,000 people took part in protests on Sunday in the country's capital of Skopje, marching from the government building to the Macedonian parliament, AFP reported. The protesters demanded the resignation of PM Gruevski's government, following opposition leader Zoran Zaev's accusations against them and recent ethnic clashes in the ex-Yugoslav republic.

"We have to take a stand and confront the criminals. They belong in jail, not in government," a demonstrator told Reuters. The protesters carried pictures depicting Gruevski behind bars.

The crisis, which has already been named the worst political unrest in the country since 2001, started to unravel in February, when the opposition leader released illegally gathered wiretaps alleging the government has been breaking some fundamental democratic rules. The prime minister said the tapes were doctored.

While an election is not due in Macedonia until 2018, Zaev has been calling on Gruevski to resign, with some demonstrators now saying they plan to camp out in the streets until this happens.

"The protest will continue. Some 4,600 activists, mostly young people, have said 'we'll stay regardless of whether you will or not'," the opposition leader told the NOVA online television channel, as cited by AFP.

The government leader has called his own rally for Monday, Reuters reported.

This month, Macedonia has seen the worst violence in decades, after clashes between ethnic Albanian rebels and Macedonian police in the town of Kumanovo not far from the Kosovo border left 18 people dead, including eight police officers. At least 30 people, most of them Kosovar Albanians, have been charged over the attack in the ethnically diverse city that has a strong Albanian presence.

The clashes were the worst since the 2001 insurgency, when the ethnic Albanian National Liberation Army (NLA) militant group, a KLA offshoot, began attacking security forces in Macedonia, demanding greater rights and autonomy for the country's Albanian minority. In response, NATO sent 3,500 troops to the region.

READ MORE: Macedonians rally for government resignation amid surging political unrest

Following the shooting in Kumanovo, ambassadors from the US, France, Italy, the UK, Germany, and the EU issued a joint statement threatening to “undermine” Macedonia's decade-long road towards EU and NATO membership.

Calling Macedonia a "tinderbox," political analyst Aleksandar Pavic said the current crisis "is not the first time we've seen such unrest that is ethnically motivated and instigated from the outside." Macedonia suffered a similar situation in 2001, "after which America and the Western powers came in and brokered peace that gave Albanians much more power than they had before," Pavic told RT.

"We must remember when the South Stream gas pipeline was on board, Bulgaria was also a target of destabilization, there were also people in the streets, and as a result Bulgaria was the key country that withdrew support from South Stream. That's when Russia turned to Turkey for the Turkish Stream, and as soon as Russia and Turkey made a deal, we have unrest in Macedonia," Aleksandar Pavic told RT.

READ MORE: Macedonia terrorist raid may be linked to country's support of Russia – Lavrov

Earlier this week, Russian Foreign Minister Sergey Lavrov said that Moscow "can't help thinking" that the recent terrorist attack in Macedonia has something to do with the country's objection to anti-Russian sanctions and its possible role as a transit country for Russian gas through Turkey.

During his visit to Serbia on Friday, Lavrov expressed concern that events in Kumanovo "were the result of a well-planned terrorist act," and said the situation in Macedonia "does not give us any grounds for optimism." Officials in Brussels are apparently embarrassed that all their efforts to stabilize the situation in the former Yugoslavia have been ineffective, Lavrov added.

Fearing ethnic tensions could escalate amid the current political instability, the Russian Foreign Ministry said that reigniting chaos in the Balkans would pose a direct threat to Europe.