Imran Khan's arrest is an abduction, an attack on the judiciary, and a slap on Pakistan's democracy. The country's ruling political elite doesn't want the PTI chief back in power in any capacity and will go to any extent to prevent him from proving his legitimacy to fight the upcoming general elections.
The former prime minister was arrested in a case involving the embezzlement of $239M. He has often used religion to garner support, manipulate the judiciary to his whims, and exploit the country for his petty political objectives. If his arrest is politically motivated, as he claims, he will have a chance to prove this before the anti-graft court.
There's a 27% chance that India will conduct a military intervention against Pakistan before the 2024 Indian general elections, according to the Metaculus prediction community.