“I am disappointed that the social media activist has been arrested,” the prime minister said on Twitter.

Police arrested Firdaus Abdillah Hamzah in Pahang before bringing him to Johor.

Firdaus, who runs a current affairs website called Neon Berapi, had in the past taken potshots at Tunku Ismail on social media.

But Tunku Ismail has distanced himself from the arrest, saying the Johor palace never lodged any complaint with the police.

“This has nothing to do with us and please, in this holy month, my family and I would like to carry out our official duties to be with the people and perform rituals,” he said on Twitter.

Mahathir meanwhile said people should be allowed to criticise their leaders.

“Freedom of speech is important in a democracy. With the exception of threats, slander or insults towards ruling monarchs, any leader can be criticised without affecting the right of the people to voice out,” he said.

Johor police chief Mohd Khalil Kader Mohd, in a statement today, said the arrest followed a police report lodged in Tampoi on May 4 by a 37-year-old man who was unhappy with a tweet by an account holder named Pipiyapong.

He said the tweet appeared defamatory and was aimed at Tunku Ismail.

“An investigation paper was opened under Section 504 of the Penal Code and Section 233 of the Communications and Multimedia Act.”

Under Section 504 of the Penal Code, any offender charged with disturbing public peace can be jailed for two years or fined, or both, if convicted.

Under Section 233 of the CMA, which deals with improper use of network facilities, the offender can be fined RM50,000 or jailed up to a year, or both, if convicted.

Khalil said the suspect, aged 36, was arrested yesterday at 11.15am in Kuala Lipis, Pahang, for further investigations. He was released on police bail today.

Police however did not reveal the name of the suspect.