Task: Question Answering
Input (English): Passage: Sanders is a British colonial District Commissioner in Colonial Nigeria. He tries to rule his province fairly, including the various tribes comprising the Peoples of the River. He is regarded with respect by some and with fear by others, among whom he is referred to as "Sandi" and "Lord Sandi". He has an ally in Bosambo, a literate and educated chief (played by the American actor, Paul Robeson).
When Sanders goes on leave, another chief, King Mofolaba, spreads the rumour that "Sandi is dead." Inter-tribal war seems inevitable, and the situation is made worse by gun-runners and slavers.
His relief, Ferguson (known to the natives as Lord Ferguson), is unequal to the task; he is captured and killed by King Mofolaba. Sanders returns to restore peace. When Bosambo's wife Lilongo is kidnapped, the chief tracks down her kidnappers. Captured by them, he is saved by a relief force commanded by Sanders. Bosambo kills King Mofolaba and is subsequently named by Sanders as the King of the Peoples of the River. 
Question: Who is captured while looking for his wife and then saved by a relief force?
Output (English): Bosambo.