In total, how many Theban people were either killed or captured according to the article? Who was the leader behind this attack on Thebes? The article is pasted below:
After Phillip's death, several towns and territories under Macedonian control tried to break free. While young Alexander was busy getting the northern kingdoms of Thrace and Illyria back in line, the Greek leaders of Thebes heard a rumor that Alexander had actually been killed in battle.

No such luck. When Alexander received word that the Macedonian garrison in Thebes was under attack, he and his army flew to the fight, supposedly covering 300 miles (482 kilometers) in just 12 days. In the ensuing Battle of Thebes, Alexander decided to send a clear message. Anyone who crosses Macedonia will not only be defeated, but obliterated.

According to the Greek historian Diodorus of Sicily, 6,000 Theban soldiers and citizens were killed and 30,000 captured before the city was burned to the ground. He wrote:

All the city was pillaged. Everywhere boys and girls were dragged into captivity as they wailed piteously the names of their mothers. In the end, when night finally intervened, the houses had been plundered and children and women and aged persons who had fled into the temples were torn from sanctuary and subjected to outrage without limit.
The tactics were cruel, but the message was received. Alexander was the undisputed new ruler of the Greeks.
In total, 36,000 Thebans were either killed or captured. The leader behind the attack on Thebes was Alexander. 