'To call it medieval is counter-productive'

It is dangerous and misleading to brand Islamic extremists as "medieval”, according to a terrorism expert.

Actions of groups such as so-called Islamic State are profoundly contemporary and often ahead of the curve, said Jason Burke, citing the group's crowd-funding techniques as an example.

"Islamic State have developed this strategy of using horrific very intimate violent executions... because they can make us see it," said the author and journalist.

Burke's latest book - The New threat - argues that in order to counter Islamic extremism, the West needs to better understand how such groups are operating.