Pakistan launched air strikes on Kabul and other Afghan cities early on Friday, marking the most serious escalation between the neighbours in months and prompting Islamabad to declare “open war” on the Taliban authorities. Jets struck targets in the Afghan capital at about 1:50am local time, according to Al Jazeera , which cited its correspondent in Kabul. Residents reported loud explosions and anti-aircraft fire over the city. Blasts were also heard in Kandahar and in Paktia province.