SOFIA (Reuters) - Bulgarian authorities have charged a Swiss citizen with terrorism and arms smuggling after he was arrested trying to cross the border with Turkey to reach Syria, the prosecutors office said on Thursday.

The man, wanted by the Swiss authorities, was captured in an operation by the national security service, border police and prosecutors at the Kapitan Andreevo border check point on Sept. 11 and charged the following day, prosecutors said.

During the search of his Swiss-registered SUV, police found three rifles, a pistol, more than 400 rounds of ammunition and at least 24 knives. They also founded a map with a route that ended in Syria’s northern Idlib province.

The prosecutors did not reveal the man’s name. They said his father had alerted the Swiss authorities that he was missing along with the SUV, weapons and ammunition. They quoted the suspect as saying he wanted to go help civilians in Syria.

Idlib and parts of a few neighboring provinces form the last major stronghold in Syria of opponents of President Bashar al-Assad, and government forces have threatened to launch a major offensive to capture the area.