They are also "monitoring the situation on the ground," the Beta news agency reported on Wednesday.

"There is certainly a greater security challenge here. We have determined our priorities and are taking necessary measures," the local Radio Sto Plus was told by the Novi Pazar police.

Novi Pazar is the largest town in Serbia's southwestern Raska District, known informally as Sandzak, which borders Bosnia and has a large Bosniak (Muslim) minority.

In the wake of the attack in Zvornik, located on the border with Serbia, when a police officer was killed, the Serbian police raised the level of security throughout the country.