KUALA LUMPUR, Malaysia — Malaysian police arrested a woman Wednesday in the apparent assassination of Kim Jong Nam, the North Korean leader’s exiled half brother who South Korean spies say once begged his sibling to spare his life. According to two senior Malaysian government officials, who spoke on condition of anonymity because the case involves sensitive diplomacy, the elder Kim died en route to a hospital on Monday after suddenly falling ill at the budget terminal of Kuala Lumpur International Airport. Multiple South Korean media reports, citing unidentified sources, said two women believed to be North Korean agents killed him with some kind of poison before fleeing in a taxi. [...] Wednesday, Malaysian police arrested a woman carrying Vietnamese travel documents bearing the name Doan Thi Huong at the Kuala Lumpur airport budget terminal, where Kim Jong Nam was attacked. Since taking power in late 2011, Kim Jong Un has executed or purged a number of high-level government officials in what the South Korean government has described as a “reign of terror.”