Bosnian police arrested 11 people on Tuesday for suspected links to Islamic State and other groups fighting in Syria and Iraq, a day after detaining five people for allegedly smuggling guns and other arms to Germany.

The raids come as Bosnia and its Balkan neighbours come under closer international scrutiny over hundreds of their citizens who have travelled to warzones in the Middle East, and due to the region’s burgeoning black market in weapons.

“The objective of this major operation was to track down some 15 people who … are close to radical groups and the structures of the Islamic State, as well as people who are on the battlefields in Syria or Iraq,” the Bosnian prosecutor’s office said in a statement.

Police inspector Marina Zulic said 11 people had been arrested for suspected links to “terrorism, financing of terrorism, inciting and organising criminal acts, and recruiting fighters for wars in other countries.”

Police agents raided a number of locations, including private houses that were used for prayer meetings by Islamic preachers who are not sanctioned by Bosnia’s Islamic Community, which oversees and regulates the country’s mosques.

These “unofficial” preachers are blamed for propagating radical Islam among Bosnians, more than 150 of whom are thought to have joined Islamic State, also known as Isis, with several dozen believed to have been killed in Syria and Iraq.

Bosnian security services also monitor men from the Middle East and north Africa who settled in the country after fighting in its 1992-5 war, and who are seen as another potential source of radicalism and inspiration for would-be jihadists.

Bosnians, Kosovars and Albanians have joined Islamic State, and in June – on the eve of Pope Francis’ visit to Bosnia – the terror group released a slickly produced film in the Bosnian and Albanian languages appealing for more Balkan recruits.

Some of the raids conducted on Monday took place in the Rajlovac area of the nation’s capital, Sarajevo, where last month a man shot dead two Bosnian soldiers and then killed himself in what police are treating as a terror attack.

The police launched the operation a day after they arrested five suspected arms smugglers and seized a large cache of guns, ammunition and other weaponry.

It is not clear if the arrests are linked to the attacks in Paris on November 13th which killed 130 people, but Serbia’s Zastava arms factory has said it made some of the guns used by the assailants, and German media have reported that some of the weapons were bought from a smuggler in Germany.

After the Paris attacks, Balkan states vowed to target a major black market in arms that generates large sums for mafia groups, thanks to the easy availability of ex-military weapons in the region, often-lax law enforcement and rampant corruption.

In another series of raids on Monday, Bosnian police arrested at least 10 people allegedly involved in smuggling at least €15 million in cash out of the country, in a scheme that is believed to have involved Bosnian and Chinese citizens.