Saudi Arabia’s counter-terrorism law passed by the council of ministers in December 2013 went into effect on Saturday.
The legislation, made up of 40 clauses, is meant to combat terrorism and impose tough penalties on those who fund it.
It defines terrorism as any act with a criminal motive that directly or indirectly undermines public order  and the state’s security and stability, or endangers national unity.
The law gives security forces the right to arrest and hold a suspect for up to six months with the possibility of extending the detention for another six months.
The ministry of interior is charged with issuing arrest warrants to those suspected of committing terrorism-related crimes.
Activists have voiced concern that the law is too broad and could be used to silence those calling for democratic reforms.