Serbian authorities said they had uncovered a plot by "criminal clans" to bring down a government plane carrying a national leader, in the latest twist to a murky row over the links between the mafia and politicians.
In a statement, the Interior Ministry said Prime Minister Ivica Dačić, who is also interior minister, had nevertheless decided to board one of the government's two planes for his return to Belgrade from Dublin on Thursday (14 February).
The Serbian leader was in Ireland hoping to secure a date from EU leaders for the launch of accession negotiations. Serbia received candidate status in March 2012.
Dačić is at the centre of a row over links between him and his aides to an alleged drug smuggler, following a series of revelations in the Serbian press this month that have rocked the six-month-old ruling coalition.
He has admitted meeting Rodoljub Radulović, known as Misha Banana, in 2008 and 2009, but denied any wrongdoing.
Dačić says he is being targeted by forces trying to halt the government's fight against organised crime and corruption.
Some analysts, however, suspect political gamesmanship within Dačić 's coalition government, with his partners, the increasingly-popular Serbian Progressive Party (SNS), eyeing a snap election that would almost certainly cement its hold on power. The SNS denies waging a smear campaign.
The ministry statement said the intelligence service had discovered that "certain criminal clans", working with individuals with access to the government aircraft, planned to induce a malfunction during a foreign trip by either President Tomislav Nikolić, Dačić or SNS leader Aleksandar Vučić, who is leading the crackdown on organised crime.
The statement noted that the government's official planes have been prone to malfunction.
Serbia is still wrestling with the nexus of crime and politics that took root during Yugoslavia's bloody collapse in the 1990s, and is no stranger to political assassination.
Zoran Djindjić, the country's first prime minister after the overthrow of late strongman Slobodan Milošević in 2000, was shot dead in Belgrade in 2003 in an assassination carried out by former members of an elite police unit working with the mafia.
The interior ministry and Serbian security services are notoriously factional and used as political levers by rival parties.