Citing intelligence reports, the German magazine Der Spiegel reported that Ahmed Wali Karzai -- head of the provincial council in Kandahar -- also heads an organization that provides protection for drug traffickers in southern Afghanistan.
Afghanistan is the world's leading supplier of opium, accounting for 90 percent of the world's supply. The United Nations estimates that more than half the country's gross domestic product comes from drug trafficking.
The president denies that his brother is involved, but has asked Ambassador Ronald Neumann to conduct an independent investigation.
Video of Victoria’s Secret models trying to 'twerk' hits Instagram
Susan Sarandon: I was stoned at almost every awards show