Imran Farooq murder: Two men sought by UK authorities
30 January 2014 Last updated at 02:33 GMT
UK prosecutors have asked Pakistan to trace two suspects believed to have been involved in the 2010 murder of Imran Farooq, a senior leader of the Muttahida Qaumi Movement (MQM).
He was stabbed outside his home in Edgware, London, close to the Pakistani political party's international HQ.
Documents obtained by BBC Newsnight name the suspects as Mohsin Ali Syed and Mohammed Kashif Khan Kamran.
They are believed to be in Pakistani custody but not under formal arrest.
Owen Bennett-Jones reports for Newsnight.