Three Syrians living in Germany have been arrested in Bulgaria on their way to join Islamic State fighters back home and are facing terrorism charges, prosecutors in Sofia said Tuesday.
It is the first such case in Bulgaria since it introduced new legislation last year criminalising the intent of joining terrorist groups.
Police detained the men -- aged 21, 22 and 25 -- last week as they tried to illegally cross Bulgaria's southeastern border with Turkey, near the main Kapitan Andreevo checkpoint.
Bulgarian newspaper Capital reported Tuesday that the Syrians were refugees residing in Germany for between two and six years, meaning they did not arrive with the recent influx of migrants.
After their February 8 arrest, the suspects had initially been handed six-month suspended sentences for trespassing.
However, authorities then found "pictures with jihadist content on their mobile phones and tracked down correspondence between them and Islamic State members who are well known to European authorities," the special prosecution's press office told AFP Tuesday.
The trio denied the allegations, but authorities said that several witnesses had confirmed the suspects' intention to join fighters in Syria.
They had tried to enter Turkey earlier this year after travelling by bus from Germany to Greece, but had been turned back, according to officials.
Bulgaria, which has remained on the sidelines of the huge migrant influx from Turkey and Greece to Europe, has become a major transit country for jihadists seeking to join IS in Syria.