Bersih chairperson Maria Chin Abdullah has filed a defamation suit against Sungai Besar Umno chief Jamal Md Yunos for alleging that the electoral watchdog is infiltrated by the Islamic State (IS).

The suit was filed on her behalf by lawyers N Surendran and Melissa Sasidaran as Maria is currently in Kedah launching a Bersih event.

"Maria is suing Jamal for defamation because of words that Jamal uttered at a press conference on two different occasions over the past week.

"In those press conferences, he claimed that Bersih was infiltrated by IS and such things. So this is clear defamation from our client's point of view," Surendran told reporters after filing the suit with the High Court in Kuala Lumpur.

Since Maria is the chairperson of Bersih, and Bersih was accused of the allegations, he said that constituted as defamation on his client.

Citing Jamal’s "toilet bowl stunt", Surendran, who is also PKR's Padang Serai MP, confirmed that Maria was also seeking aggravated damages.

On Wednesday, Jamal (photo), who heads the red shirts movement, tore up Bersih's letter of demand for an apology and flushed it down the toilet, in front of members of the media.

Surendran also confirmed that Maria was also filing an injuction to stop Jamal from repeating the "absurd" allegation.

"We filed the defamation suit this morning, which means this matter must come up to trial.

"And there, Melissa and I will question him and we will expose all these allegations against our client as utter lies," Surendran said.

Contacted later, Jamal said Bersih was free to do what it wanted as it has the right to do so.

"They are using their right because they are probably unhappy over what I said.

"They claimed that the EC is not transparent, that (prime minister) Najib (Abdul Razak) is corrupt. Well, we have legal avenues to challenge this instead of holding rallies," Jamal said.

"Whatever they do, I will defend what I have said and done. We will meet in court," he added.