Bosnia's state court has ordered one-month detention for five Islamists charged with organising and recruiting people to fight for radical groups in Syria and Iraq, the court said on Monday.

The five were among 16 people who were detained last week in police raids across Bosnia on charges of financing terrorist activities and recruiting and fighting abroad, the first such security sweep since jail terms of up to 10 years were introduced in April for those activities.

The move was aimed at discouraging young Bosnians from going to fight in Syria. Most Bosnian Muslims, known as Bosniaks, practice a moderate form of Islam but some young Muslims have embraced the ideas of the puritanical Sunni Wahhabi sect.

The five detainees were suspected of "organising a terrorist group and ... recruiting for terrorist activities," the court said, adding they should be detained to prevent them fleeing, influencing witnesses or continuing their activities.

Local media have reported that three of the detainees have fought and returned from Syria. A fourth, Husein Bosnic, known as the unofficial leader of the ultra-conservative Salafi movement in Bosnia under the name Bilal, has never been to Syria but has publicly urged young Muslims to join the Islamic State.

His lawyer said that Bosnic was charged with acts he had committed before the law came into force and that he would file an appeal against the detention.

During the Wednesday's raids, police confiscated a large amount of weapons and ammunition.

So far prosecutors have questioned nine out of the 16 people originally held last week. As well as the five detention requests, they have asked that the other four questioned suspects should be placed under house arrest.