Senior Superintendent David Quimio, city police chief, identified the five suspects as Jaime Ilejorde, 43, of Barangay Lumbang; Romulo Manaloto, 31; of Barangay San Jose; Teodoro Garing, 40, of Barangay Bolbok; Russel Villapando, 32, of Barangay Bagong Pook; and Virgilio Hernandez, 47, of Barangay Balintawak.
All five were supporters of mayoralty candidate Ruben Umali.
Police nabbed the five men along C.M. Recto Avenue in Barangay 6 based on information from Juliet Marasigan and Andres Oriño, both coordinators of Santos, that a group was distributing cash and T-shirts emblazoned with Umalis face, in Purok 2, Barangay Lodlod at about 12:45 a.m.
Reports said the suspects allegedly offered P250 to people willing to vote for Umali and were asked to sign up. A yellow pad paper seized from them bore 137 names.
Police confiscated P31,500 in different denominations in 12 bundles, T-shirts with the words "Full-Time Mayor," and a poster of Umali. Their Mitsubishi pick-up was impounded.
Lawyer Socrates Hermoso, Umalis legal counsel, said the arrest was "pure harassment."
"Ang hawak nilang pera ay pambayad sa aming watchers at doon nakasulat sa yellow pad paper (The money they had was for our poll watchers whose names were on the yellow pad paper)," he said.
Santos is seeking a third and last term. Umali served as mayor for three consecutive terms until 1998 when Santos defeated his son King.