A senior female Pakistani politician has been shot dead in the southern port city of Karachi. Zahra Shahid Hussain was the senior vice-president of Pakistan’s Movement for Justice party (PTI), led by former international cricketer Imran Khan. She was killed by gunmen on a motorcycle outside her home in the city’s upmarket Defence neighbourhood. Her murder took place on the eve of a highly-contested partial re-run of last weekend’s general election. The reason for the shooting is unclear. PTI leader Imran Khan