The infamous Operasi Lalang resulted from the discord between MCA Youth and Umno Youth, whose acting chief then was Prime Minister Najib Abdul Razak, according to Anwar Ibrahim.

"That was the real reason for the arrests," he said.

Anwar, who was Umno vice-president at the time, was testifying at the hearing of Bersih chairperson Maria Chin Abdullah's defamation suit against Sungai Besar Umno division chief Jamal Md Yunos (photo) at the Kuala Lumpur High Court this afternoon.

The former opposition leader said the tension between MCA Youth and Umno led to others being arrested under the Internal Security Act (ISA), including Maria's late husband Yunus Lebai Ali.

A total of 106 people, including opposition politicians and activists, were arrested during Operasi Lalang under the now-defunct ISA, which provided for detention without trial.

In his testimony, Anwar claimed he had pleaded with the then prime minister and home minister Dr Mahathir Mohamad to release those not involved in the MCA Youth-Umno Youth squabble.

He said former finance minister Daim Zainuddin (photo) was also present when he met Mahathir at his official residence in Sri Perdana.

"However, Mahathir said let the police and special branch deal with this," he added.

Reports indicated that there were race and religion-related issues during that period, including the Education Ministry's decision to appoint 100 senior assistants and supervisors to Chinese medium primary schools.

This led to prominent leaders from the Chinese community to hold a gathering with some 2,000 people at the United Chinese School Committees Association of Malaysia. Also present were MCA's then-president Lee Kim Sai and DAP's Lim Kit Siang.

Following this, Umno Youth held a mammoth counter-rally at Kampung Baru.

Jamal's lawyer, Mohd Nasser Yusof, had questioned Anwar on the reason behind the arrest of Maria's husband.

The Bersih chairperson filed the suit against Jamal following his accusation that the electoral watchdog is linked to the Islamic State terror network.

Anwar was also asked about his experience as a student leader in Universiti Malaya along with Yunos and activist Hishamudin Rais.

He said they participated in various demonstrations including the one in Baling, Kedah, on the plight of rubber tappers and the poor in 1974, the war in Vietnam, the occupation of Palestine and United States' support for Israel.

Anwar also said during the demonstration held outside the US embassy in Kuala Lumpur, the student leaders had a dialogue with then home minister Ghazali Shafie.

He pointed out that political leaders then were prepared to meet with students, unlike present leaders.

Anwar also denied Nasser's suggestion that the Palestine Liberation Organisation (PLO) is a terrorist organisation.

"When I was a minister in 1983, I also invited PLO leaders to UiTM," he said.

When Jamal's lawyers had cross-examined Maria, they had described PLO as a terrorist organisation.

Maria's husband had served as late PLO leader Yasser Arafat's bodyguard at one time.

The Bersih chairperson is represented by N Surendran and Latheefa Koya. The trial continues before Justice Mohd Zaki Abdul Wahab on March 5.