PETALING JAYA, Nov 21 — Former prime minister Tun Dr Mahathir Mohamad said he would repeat his actions in the notorious Ops Lalang security crackdown of 1987 under the same circumstances today.

Speaking at a town hall session with youths here tonight alongside DAP parliamentary leader Lim Kit Siang, one of those detained using the Internal Security Act (ISA) in the dragnet, Dr Mahathir also insisted that his actions had not been an "abuse of power”.

"I have to listen to my security adviser. Under the same situation, I would have to arrest them (detainees),” Dr Mahathir said, claiming that many of the ISA detentions during his rule had been to prevent racial tension from escalating in the country.

He also said that that he would be failing his duty if he had not taken action following security forces' advice.

After Ops Lalang, the ISA gained a reputation for being a "white terror”, as the incident demonstrated the ease with which the colonial era security law could be applied on political dissidents.

Tonight, Dr Mahathir was also adamant that the ISA had not been used solely against political dissent.

"They (previous governments) did not abuse their power. Not all of ISA arrests were politically motivated,” he said.

The law was eventually repealed in 2012 by Prime Minister Datuk Seri Najib Razak.

Continuing to defend himself on the ISA, Dr Mahathir also insisted that he made fewer arrests using the law than his predecessors.

He pointed out that he detained 1,200 using the ISA over his 22-year administration, versus more than 2,000 by the three prime ministers before him.

Dr Mahathir did not point out, however, the fact that the communist threat only ended in 1989 with the dissolution of the Malayan Communist Party; the ISA had been among laws enacted to combat the menace.

"Tunku Abdul Rahman, Tun Abdul Razak, and Tun Hussein Onn all arrested more people under the ISA, yet I am the one who gets [criticised,]” he said.

He defended the need for preventive detention laws in the country to maintain law and order.

Some former detainees of Ops Lalang continue to demand for Dr Mahathir to openly apologise over the incident.