This was revealed via his Twitter account earlier.
"I was detained under the Peaceful Assembly Act and 143 of the Penal Code for one night at the Dang Wangi and will be brought to Jinjang," said the Seri Setia assemblyman.
It is understood that Nik Nazmi was detained under Section 9 (5) of the Peaceful Assembly Act and Section 143 of the Penal Code and will be brought to the Jinjang police station where he will be remanded until tomorrow.
Earlier, Nik Nazmi had been called to provide statements on the #KitaLawan rally which happened on Saturday.
In his tweet last night, he said received a call from a police officer asking him to come to the Dang Wangi district police headquarters today.
"I informed that I will be present tomorrow (Sunday) 10am with a lawyer," he had said in his 10.20pm tweet.
![kitalawan](http://img.astroawani.com/2015-03/71425808362_freesize.jpg)
The final #KitaLawan rally on Saturday saw some 5,000 people gathering in the city centre to show their solidarity for Anwar. - Astro AWANI
Meanwhile, his lawyer Melissa Sasidaran denied the accusation that her client had been detained for repetitive offense.
"Yes, I was informed they would arrest Nik Nazmi because he is a repeat offender as an organiser.
"But it is wrong as Nik has been charged multiple times in court, and if I am not mistaken as many as four times for Black 505, and he is not an offender because he was not sentenced by the court," he told reporters when met outside the Dang Wangi police district headquarters.
She said, Nik Nazmi had been informed that that he would be remanded tomorrow starting at 10am but was not sure whether he would be remanded in Dang Wangi or Jinjang.
"So we will be notified tomorrow morning... and tomorrow I will be in touch with ASP Sabri and inform all," said Melissa.
She said she was also informed by the police that the remand was a "directive" but was not sure who gave it.
Yesterday, Kelana Jaya PKR Youth chief Zulkifli Saifullah was arrested under the same Act immediately after the assembly.
This was revealed by PKR communications director Fahmi Fadzil via WhatsApp at around 8.10pm Saturday night.
Prior to this, Inspector-General of Police Tan Sri Khalid Abu Bakar had warned the rally organisers to be ready for any police action.
The #KitaLawan rally was held to show support for PKR's Datuk Seri Anwar Ibrahim, who, on Feb 10, had his previous sodomy conviction upheld against him.