An IS supporter said to have bludgeoned an imam to death for practising "black magic" is at large after he flew to Turkey in the days that followed, a jury has heard.
Mohammed Abdul Kadir, 24, allegedly developed "a hatred" of Jalal Uddin, 71, over his form of Islamic healing which involved making amulets to bring good fortune to the wearer.
Manchester Crown Court heard that IS considered such practises as forbidden and that the terror group had beheaded magicians.
The Crown say Bangladeshi national Mr Uddin was targeted by Kadir as he walked through a children's play area in Rochdale, Greater Manchester, on February 18.
Three days later, Kadir, of Chamber Road, Oldham, boarded a flight from Manchester to Copenhagen in Denmark followed by a connecting flight to Istanbul.
The whereabouts of Kadir are unknown although it is thought he may have travelled to Syria, the jury was told.
But his associate, Mohammed Hussain Syeedy, 21, also said to be an IS follower, is in the dock accused of murder.
Syeedy, of Ramsay Street, Rochdale, is said to have acted as the getaway driver on the night of the attack with the prosecution saying he knew full well that Kadir intended to kill or seriously harm Mr Uddin.
When arrested, the defendant gave a statement which read: "I am not guilty of any offence in relation to the death of Mr Jalal Uddin. I make this statement believing it to be true and that it may be produced in evidence."
Police found a large volume of IS-related material on various devices said to belong to Syeedy at his family home, including many photographs of him and his friends - including Kadir - raising IS one-finger salutes.
Prosecutor Paul Greaney QC told the jury: "Our submission is that the combination of circumstances demonstrates beyond doubt that Mohammed Hussain Syeedy intentionally assisted and encouraged an attack by Kadir upon Jalal Uddin that was intended to cause that man really serious harm, if not kill him."
Mr Uddin suffered multiple injuries to his head and face in the attack, thought to have involved a hammer, in South Street, Rochdale, after he visited his local mosque for evening prayers and a friend's house for a meal.
His form of healing - Ruqya - involved the use of amulets, known as taweez.
IS is said to follow a trend in Islam known as Salafism, whose followers argue Islam has strayed from its roots and should return to the practice of the seventh century, the court heard.
Giving expert evidence, Professor Robert Gleave, Professor of Arabic Studies at the University of Exeter, said: "For Salafis, if the person prepares a taweez they have committed a sin but someone who continuously practises has moved into the area of unbelief."
Prof Gleave said punishment for continuous practice would be execution, while he added that IS had been known to behead people who it considered to have practised magic.
He said Ruqya was "usually seen as a positive form of magic practised by experts and providing a service to the community", to either protect people from harm or give a blessing such as wealth or conception.
He added there was also a view that the supernatural world existed but it should not be "meddled in".
Syeedy denies murder.