Murder of Croatian reporter undermines EU hopes

"From now on, no criminal can sleep calmly," he added, pledging to introduce "extraordinary mobilisation measures," details of which should be announced later this week.

The statement came after Ivo Pukanic and Niko Franjic, who both worked for an influential newspaper, Nacional, were killed by an explosive device placed near their car in Zagreb. Mr Pukanic, a 47-year old investigative journalist, had previously faced a murder attempt.

Earlier in October, the daughter of a prominent lawyer was shot dead in a stairwell - an event that led to the dismissal of the interior and justice ministers as well as the head of the national police.

The presence of organised crime is damaging the Croatia's EU bid, with the European parliament's rapporteur on Croatia, Hannes Swoboda, describing the latest murder as "a shock that pushes Croatia back in its ambitions to become a member of the EU."

"The government must succeed in its efforts to bring about order and so eliminate the apathy demonstrated in these last few months and years, or there will be no early entry for Croatia into the EU," he warned, according to AFP.

EU-Croatia accession talks were launched in 2005. The country is hoping to finalise them next year and become the EU's 28th member by 2011 at the latest.

The country's president, Stipe Mesic, also admitted that Zagreb faced "an unprecedented challenge from criminal circles. Now it is them or us ...rule of law and the safety of citizens versus criminals, terrorists and mafia."

The European Commission, for its part, "strongly" condemned the criminal attack, expressing trust that the Croatian authorities would "duly investigate this attack and bring the perpetrators to justice".