Pakistani paramilitary forces raided the headquarters of a powerful political party in the port city of Karachi on Tuesday after supporters of the party stormed the office of a television channel the day before.
The operation deepened a dispute between Muttahida Qaumi Movement (MQM), which has dominated Karachi politics for decades, and local security forces that regularly deteriorates into violence.
It also comes as Karachi, a metropolis of 20 million people and home to the stock exchange and central bank, is set to formally swear in imprisoned MQM politician, Waseem Akhtar, as mayor on Wednesday.