The mayor of a state capital in southern Mexico has been killed just one week after he took office, officials said Sunday.br br Alejandro Arcos was sworn in last Monday as mayor of Chilpancingo, a city so violent that a drug gang openly staged a demonstration, hijacked a government armored car and took police hostage in 2023 to win the release of arrested suspects.br br Chilpancingo is the capital of Guerrero state, where Acapulco is located.