Why did Balochistan separatists kill 26 people in railway station suicide bombing?

A suicide bomber blew himself up at a train station in restive southwestern Pakistan on Saturday, killing at least 24 people, including soldiers and railway staff, and wounding about 50 others, some critically, officials said. For more information, FRANCE 24's William Hilderbrandt interviews Ayesha Siddiqa, Senior Fellow at Kings College Department of War Studies in London.