Government troops and opposition tribesmen are battling to control key sites around Yemen’s capital of Sana. Yemen’s security forces have moved to forcibly contain many groups of opponents, and at least 41 people have died in the process. Since last week, government forces have been fighting tribal fighters loyal to the family of Hamid al-Ahmar, the strongest tribal rival of President Ali Abdullah Saleh, and this continued Wednesday as forces fired shells at tribal fighters around the headquarters of Yemen’s state-run television station. Tribesmen now control many areas of the Hasaba neighborhood, including many ministries and government buildings, though the government denied that the Interior Ministry had been overrun. Many countries are withdrawing their diplomats because of the violence; the U.S. Embassy remains open but advised all Americans to leave the country last week.