He said a lawyer of Senate colleague Aquilino Pimentel Jr., a certain Attorney Pacuribut, discovered the fraud in Bacolor town while watching the canvassing of votes.
He said an election officer, whom he did not name, tried to remove a zero from the total number of votes he received in the town.
"Attorney Pacuribut noticed the fraud and called the election officer’s attention. I had 6,030 votes and they tried to make it appear I got only 603 votes. They tried to cheat me of at least 5,000 votes," he said.
He added that had the official succeeded in deducting more than 5,000 votes from him, these could have been added to another candidate’s votes.
The former Philippine National Police chief pointed out that similar "bawas-dagdag"operations could have taken place in many parts of the country.
He said the incident would be part of the evidence he and other opposition candidates would present to prove there was massive cheating in the elections.
Lacson, his opposition rival, movie actor Fernando Poe Jr., former senator Raul Roco, and televangelist Eddie Villanueva had agreed to work together to document cases of election fraud.
Lacson also questioned the decision of the Commission on Elections to relieve its election officers in Quezon province, Nueva Ecija and Quezon City while the vote-count was going on.
"The relief orders supposedly came from the Comelec main office in Manila. The election officers may have been reshuffled because they did not comply with the Comelec hierarchy’s wishes," he said.
He said he could not understand why the poll body would pull out its officers during a "crucial time in the counting."
Earlier, Lacson said he would not concede until the last vote is counted. — Jess Diaz