Firm’s former investigator claims he was unfairly dismissed for raising concerns over 2017 attack on Tundu Lissu

Gunmen tried to assassinate a Tanzanian opposition politician after a telecoms company secretly passed his mobile phone data to the government, according to evidence heard in a London tribunal.

The mobile phone company Tigo provided 24/7 phone call and location data belonging to Tundu Lissu to Tanzanian authorities in the weeks before the attempt on his life in September 2017.