A court in China has rejected a second appeal by the country's most famous dissident, Ai Weiwei, to drop a $2.4 million tax-evasion fine.

The 55-year-old Ai called the ruling by the Chaoyang district court "shameful."

The case is widely seen by activists as an attempt to silence the outspoken artist, who has repeatedly criticized the Chinese government for abusing the rule of law and the rights of citizens.

The case comes on the heels of a score of other high-profile cases, including the flight to the U.S. Embassy of blind, self-taught legal activist Chen Guangcheng.