Former prime minister Tun Dr Mahathir Mohamad was not given a personal invitation to attend the Nothing2Hide forum on Friday, the organisers said.
Malaysian Volunteer Lawyers Association (SukaGuam) chairman Datuk Khairul Anwar Rahmat said they had organised the forum with Prime Minister Datuk Seri Najib Tun Razak for activists and NGO leaders, a fact the former premier was aware of.
"Tun Mahathir was not personally invited, and he was gentlemanly enough to admit that when he showed up this morning.
"He felt that he needed to attend the dialogue to speak about pertinent issues and to meet the people, so we welcomed him," Khairul told reporters at the Putra World Trade Centre, Friday.
The SukaGuam chairman said he did not know that Dr Mahathir was asked to start speaking to the gathered crowd, claiming that the instruction did not come from the organisers.
"No, I am not aware as I was ushered out of the hall by police before that, when the commotion started taking place.
"I will have to check with my colleagues as to who gave that instruction," Khairul said.
Dr Mahathir had started speaking in Najib's stead when he was stopped midway through his speech by police.
Khairul said the Prime Minister did not attend the dialogue session on the advice of the police who had cancelled the event over security reasons.
The session was to allow Najib to answer the public's queries on 1Malaysia Development Berhad among other issues.
He said the organisers were also advised by the police to postpone the event after a commotion broke out outside the Dewan Tun Hussein Onn hall following Dr Mahathir’s arrival.
"The organisers would like to put on record that this event had been given the go ahead, and the Prime Minister had agreed to attend.
"However, it is regrettable that some provocative actions had taken place, and in the end, an event which was supposed to be calm and meaningful went out of control," Khairul said.
He said the organisers remained determined to hold the event at a later date, and would be in touch with the Prime Minister to reschedule.
"We will also beef up security so that untoward incidents do not recur," Khairul added.
Meanwhile, the Prime Minister's Department said in a statement that Najib had decided against attending the function after being advised by the Inspector-General of Police of "security issues on location".
"Based on the directive and advice of the Inspector-General of Police, the Prime Minister could not attend the programme," it said.