Deputy Prime Minister Muhyiddin Yassin would be fully responsible should last week's violent protests by Umno Youth escalate, said Bersih.

In a strong statement by its steering committee led by Maria Chin Abdullah, the group of civil society leaders said Muhyiddin must "bear full responsibility for fuelling the fire if the political violence spreads and escalates".

"His statement that the thugs were merely defending the party’s honour, coupled with the light attitude taken by police, has raised questions if there are deliberate moves to destabilise the country and Najib Razak’s premiership," said Bersih.

Umno Youth held three ugly protests last week and damaged DAP's premises in Kuala Lumpur and Kuantan over an alleged insult by DAP assemblyperson RSN Rayer.

While BN partners MCA and Gerakan have condemned the violence, Muhyiddin merely commented that the acts were a " natural reaction " to the insult.

"Bersih solemnly reminds Muhyiddin that his defence that Umno Youth demonstrated only to defend the party’s honour completely does not befit his capacity as the deputy prime minister," said the coalition of NGOs.

Bersih said while Umno has every right to protest against Rayer's statement, there is no room for violence in civilised politics, and using violence would only reduce politics to gangsterism.

“Bersih solemnly reminds Muhyiddin that his defence that Umno Youth demonstrated only to defend the party’s honour completely does not befit his capacity as the deputy prime minister.

“While gangsters may resort to violence to defend their honours, politicians must never do,” said the coalition of NGOs.

IGP must go if violence repeated

The group urged Malaysians to pressure Muhyiddin to retract and apologise over his statement, and for the police to act decisively against any form of political violence.

Those voting in by-elections should also voice their displeasure through the ballot box towards those who condone “thuggish behaviour,” they said.

It added that should a fourth attack occur, the inspector-general of police (IGP) Khalid Abu Bakar should resign.

“In such unfortunate development, Malaysia will need a new IGP to restore the public’s and investors’ confidence in the country’s stability.

"Malaysia cannot afford to be seen as going the way of Thailand,” Bersih said.