Manila. Philippine authorities detained seven suspects and several more were being sought in a major corruption scandal involving flood control projects, President Ferdinand Marcos Jr. said Monday as he tried to quell public outrage over the brazen anomalies that have implicated powerful members of Congress.

Massive corruption has been blamed for substandard or non-existent flood control projects in the poverty-stricken Southeast Asian country long prone to deadly floods and extreme weather. Two Philippine presidents, including Marcos’ late father, were overthrown in peaceful public revolts due to alleged plunder and misrule.

The initial batch of more than a dozen suspects, including Zaldy Co, a former member of the House of Representatives, and government public works engineers, were indicted by the Sandiganbayan, a special anti-corruption court, in the first of what is expected to be dozens of criminal graft and corruption lawsuits that Marcos promised would lock up implicated senators, House members, and wealthy construction company owners by Christmas.

The first corruption case involved irregularities in flood control projects in Oriental Mindoro province, including a river dike worth 289 million pesos ($4.8 million), that were undertaken by Sunwest Corp., a construction firm that officials say is owned by Co’s family.

Marcos said one suspect was arrested and six others surrendered over the weekend to police. The arrested suspect was found in a house in suburban Quezon city in the capital region where an unspecified number of people who were trying to help hide the suspect were also arrested, he said.

“My advice to the remaining suspects is for all of you to surrender, don’t wait to be pursued,” Marcos said in an early Monday post on his Facebook account. “This will continue, we will not stop.”

Interior Secretary Jonvic Remulla said the location of Co, who is believed to be outside the Philippines, was unknown, but three other suspects may soon surrender to the Philippine embassies in the United States, New Zealand, and Jordan and be flown back home.

“No matter where you are in the world, we will find you,” Remulla said at a news conference, where mug shots of the arrested suspects in orange detainee shirts were shown.

Witnesses have testified in Senate hearings and in an independent fact-finding commission established by Marcos that several former and incumbent senators and House members have pocketed huge kickbacks from favored construction companies, which cornered lucrative flood control contracts for years. A number of Department of Public Works and Highways officials and engineers have testified under oath in the Senate hearings that they helped arrange the corrupt deals and received large sums for doing so.

The lavish lifestyles, mansions, suitcases of cash, and fleets of luxury cars and private jets of the leading corruption suspects have sparked huge protests. An upcoming demonstration scheduled for Nov. 30 is backed by the dominant Roman Catholic church.

Those implicated include Rep. Martin Romualdez, the president’s cousin and key ally, who has denied any involvement but has stepped down as House of Representatives speaker. Former Senate President Chiz Escudero has also been accused of pocketing kickbacks and has stepped down from his post but strongly denied any wrongdoing.

Aides have defended Marcos from allegations linking him to the irregularities, saying that he first raised alarm over them in July in his annual state of the nation address before Congress.

At least 9,855 flood control projects worth more than 545 billion pesos ($9 billion) that were supposed to have been undertaken since Marcos took office in mid-2022 are under investigation. In September, Finance Secretary Ralph Recto told legislators that up to 118.5 billion pesos ($2 billion) for flood control projects may have been lost to corruption since 2023.

The anomalies may have started under Marcos’s predecessor, Rodrigo Duterte, and flood control projects undertaken in his time would also be investigated, officials said.