Detailed Instructions: You need to read the given passage and construct a question about the information present in the passage. The question should be answerable from the passage. Most importantly, only those questions are allowed whose answers cannot be determined from a single sentence. Do not generate questions that require only a single sentence to answer. Instead, try to combine two sentences and create a question from that combination. Do not create open-ended questions, i.e., the answers to them cannot be found precisely from the information provided in the passage.
Q: Paragraph- Sent 1: From Babylon, Alexander went to Susa, one of the Achaemenid capitals, and captured its legendary treasury.
Sent 2: He sent the bulk of his army to the Persian ceremonial capital of Persepolis via the Royal Road.
Sent 3: Alexander himself took selected troops on the direct route to the city.
Sent 4: He had to storm the pass of the Persian Gates (in the modern Zagros Mountains) which had been blocked by a Persian army under Ariobarzanes and then hurried to Persepolis before its garrison could loot the treasury.
Sent 5: On entering Persepolis, Alexander allowed his troops to loot the city for several days.
Sent 6: Alexander stayed in Persepolis for five months.
Sent 7: During his stay a fire broke out in the eastern palace of Xerxes and spread to the rest of the city.
Sent 8: Possible causes include a drunken accident or deliberate revenge for the burning of the Acropolis of Athens during the Second Persian War.
A:
What happened with Persepolis at the time of Alexander's stay and what caused this event?