As a member of the government during the infamous Operasi Lalang in 1987 which saw hundreds detained under the now-defunct Internal Security Act (ISA), Prime Minister Najib Abdul Razak was also responsible for the arrests, said his predecessor Dr Mahathir Mohamad.

"It's the collective responsibility of the government. If I was doing something that he thinks is wrong, he's quite free to criticise me or to object," Mahathir told reporters in Petaling Jaya today.

Najib at the time was the minister of culture, youth and sports while Mahathir held the home ministry portfolio...