Two prisoners are being held in police custody after Subhan Anwar, who was jailed for torturing and murdering his partner's two year old daughter, was found dead in his cell, the Ministry of Justice said.
Anwar, who was jailed for a minimum of 23 years in 2009 for the murder of Sanam Navsarka, is understood to have been held hostage in a cell at HMP Long Lartin in Worcestershire before he was killed.
His partner, Zahbeena Navsarka, was cleared of her daughter's murder but found guilty of manslaughter and jailed for nine years.
More top news
At least 100 people have been killed in Pakistan after an oil tanker overturned and burst into flames, according to reports.
Authorities call for government to step up funding in the wake of the Grenfell fire to help evacuate and renovate other blocks.
Donald Trump has accused Barack Obama of failing to take action over Russia's alleged interference in the US election.