Senator Panfilo "Ping" Lacson on Sunday said he is gathering informants and witnesses to build a case against Sen. Alan Peter Cayetano, declaring that the latter "belongs" in jail as their increasingly bitter public feud escalated into fresh allegations of corruption and budget irregularities. 

In a post on X, Lacson accused Cayetano of attacking his integrity and vowed to pursue legal action.

"My integrity is my first and last line of defense and I will fight to defend it with all my might. Sen. Cayetano has crossed the line by attacking it," Lacson wrote.

"As of this morning, I'm still counting informants and witnesses, directly or through intermediaries, willing to provide information and evidence to put him in his proper place — the Payatas, QC jail." 

The latest salvo came a day after Lacson defended the more than fourfold increase in his declared net worth, attributing it to legitimate real estate transactions and private business ventures after leaving the Senate in 2022.

Lacson said his wealth grew from P58.7 million in 2022 to P244.9 million in 2025 and stressed that he paid P10.5 million and P2.8 million in taxes as reflected in his income tax returns. 

He also renewed allegations that Cayetano benefited from P6.79 billion in budget insertions under the 2025 General Appropriations Act, claiming 68 of the 70 projects had already been implemented.

"Unlike Sen. Cayetano with P6.79 billion in budget insertions under the 2025 GAA, I have no insertions, a.k.a. pork barrel... and no 25 percent kickback for slope protection and other infrastructure projects," Lacson said. 

The senator further alleged that there were "ghost" flood control projects in Taguig City and claimed the city's engineer, whom he described as a "self-styled BGC boy," accumulated nearly P500 million in casino winnings while using two aliases. 

Cayetano's accusations

The exchange stemmed from Cayetano's Facebook Live broadcast on Saturday, during which he questioned the source of Lacson's increased wealth and accused the government of weaponizing state institutions against political opponents. 

Cayetano introduced what he called two competing versions of "KKK" — his own "Katotohanan, Konstitusyon at Korapsyon" (Truth, Constitution and Corruption) versus what he claimed was the government's "Kuyog, Kaso, Kulong" (Mobbing, Cases and Imprisonment). 

He alleged that administration critics are first subjected to coordinated attacks before facing criminal complaints and eventual imprisonment.

"If you become part of the opposition and speak out, they will first swarm you — whether through trolls, the NBI or relevant agencies. If that doesn't work, they file cases against you. The third step is to put you in jail," Cayetano said. 

The senator also described fellow Sen. Rodante Marcoleta, Sen. Jinggoy Estrada and former congressman Mike Defensor as "political prisoners," claiming legal institutions such as the Department of Justice, the National Bureau of Investigation and the Office of the Ombudsman were being used against government critics. 

Cayetano likewise questioned efforts to obtain Vice President Sara Duterte's bank, tax and Anti-Money Laundering Council records during the impeachment trial, arguing that similar standards should apply to public officials whose Statements of Assets, Liabilities and Net Worth had drawn public scrutiny, including Lacson's. 

The renewed exchange also comes as Cayetano faces mounting scrutiny over the Philippines' hosting of the 2019 Southeast Asian Games, where he chaired the Philippine Southeast Asian Games Organizing Committee (PHISGOC).

The National Bureau of Investigation recently revived its probe into alleged anomalies after receiving what it described as new information involving billions of pesos in public funds, including alleged unliquidated expenditures and procurement irregularities. The agency has announced it will subpoena several PHISGOC officials as part of its investigation.

The Department of Justice has defended the inquiry, stressing that the NBI is acting within its independent investigative mandate and not for political purposes, while the Office of the Ombudsman has separately reopened its review of an earlier resolution that dismissed related complaints in 2021. Ombudsman Jesus Crispin Remulla said the review is not barred by double jeopardy because no criminal case had been filed in court, although he noted it is still too early to determine whether Cayetano himself would be summoned.