Police might expand their anti-riot arsenal to include taser guns for this weekend's Bersih 4.0 rally if the situation warrants it.

Deputy inspector-general of police Noor Rashid Ibrahim said today protesters might be stunned with an electric charge if they riot, become violent or resist arrest.

"In any situation, the police will follow their standard operating procedure (SOP).

"If the situation needs to be controlled, police will use the tasers to stun the suspect, in line with their SOP," he said as reported by Oriental Daily .

Rashid said police have a small number of tasers at the moment and those authorised to use them have undergone professional training.

Police grade stun guns have a range of 35 feet.

It fires two hooks, which then deliver severe jolts of electricity to temporarily incapacitate the target.

Electoral reform movement Bersih is planning a mega rally called Bersih 4 to be held on Aug 29-30 in Kuala Lumpur, Kuching and Kota Kinabalu.

The rally is to demand four things: 1. Clean elections; 2. Clean governance; 3. Saving the economy; and 4. Preserving the right to dissent.