Police have arrested a slew of suspected terrorists in a nationwide crackdown against members and supporters of the Islamic State terror group.

According to highly placed sources, Bukit Aman counter-terrorism operatives picked up the men and women in a series of special operations, which have been ongoing since mid-last month.

It was learnt the operation was intensified after the May 17 deadly terror attack on Ulu Tiram police station in Johor, which saw two police officers killed while another seriously injured.

The sources were reluctant to reveal the exact number of arrests but...