The suspect, a minor carrying the materials in a suitcase, was arrested during a routine security search at the border post on the causeway which links the Gulf island nation to Saudi Arabia, according to a Bahraini police statement published by the official Bahrain News Agency.
The statement, which did not reveal the boy's age or name, said that he told authorities a relative who lives in Iraq gave him the suitcase to take to Bahrain. The agency report said the boy's relative in Iraq, who also was not named, is wanted by Bahraini authorities on terrorism-related charges.
Young protesters routinely clash with riot police. A number of small bombs mainly targeting security forces have killed and wounded police officers.