In answer to the OP. From the BBC website:
Senior UK imams and British Muslim community leaders have also condemned the killing.
"An attack on a British citizen is an attack on Britain and we raise our voices as a community united to deplore the actions of the terrorists Isis," Dr Qari Asim, imam of the Makkah Mosque in Leeds said.
Sayed Ali Abbas Razawi, from Majlis-e-Ulama, which represents the majority of Shia Muslims in the UK and Europe, said militants were hiding behind a "false interpretation" of Islam, describing the group as "criminals and villains".
The president of the Islamic Society of Britain, Sughra Ahmed, said: "If someone who commits such evil and such heinous crimes calls themselves the Islamic Sate, then we need to understand actually that there's nothing Islamic and there's nothing state-like or legal about the work that they're doing, about the acts that they are committing."