KABUL, Afghanistan — Two senior Taliban leaders have been arrested in recent days inside Pakistan, officials said Thursday, as American and Pakistani intelligence agents continued to press their offensive against the group’s leadership after the capture of the insurgency’s military commander last month. Afghan officials said the Taliban’s “shadow governors” for two provinces in northern Afghanistan had been detained in Pakistan by officials there. Mullah Abdul Salam, the Taliban’s leader in Kunduz, was detained in the Pakistani city of Faisalabad, and Mullah Mohammed of Baghlan Province was also captured in an undisclosed Pakistani city, they said.