He said the three leaders were DAP advisor Lim Kit Siang and PKR supreme council members N. Gobalakrishnan and Badrul Hisham Shaharin, and that they were being investigated under Section 4(1) of the Sedition Act and Section 500 of the Penal Code.
The police recorded Lim's statement at his house in Island Glades this morning while Badrul Hisham gave his statement at the Seberang Perai Tengah district police headquarters Saturday, he said, adding that Gobalakrishnan had yet to have his statement recorded.
"We received a report and began recording their statements. We hope to complete the investigation in a week," he told reporters.
Ayub said the organisers of "ceramah" (talks) were told at the time of the issuing of permits that the "ceramah" should not contain elements of sedition, slander, provocation and reference to court hearings.
"If they fail to follow the rules, we have to act to stop them from repeating it," he said.
Ayub also said that the police had received 19 reports pertaining to the by-election campaign.
"We have opened 10 investigation papers and referred two cases to the relevant agencies, such as the Election Commission and the Malaysian Anti-Corruption Commission," he said.
He reminded the candidates and their supporters, as well as the public, to adhere to the rules on polling day Sunday.
The Penanti state by-election is a four-cornered contest among a PKR candidate and three independent candidates.The BN is skipping the by-election, being held following the resignation of the PKR state assemblyman and former Penang deputy chief minister I Mohammad Fairus Khairuddin.