MANILA - A self-made Chinese billionaire who got his start in the Philippines and some of the country’s largest builders helped fund a secluded treatment center for up to 10,000 drug addicts.

President Rodrigo Duterte gave miniature jeepneys as tokens of appreciation to the businessmen as he inaugurated the facility that is tucked away in Fort Magsaysay, a sprawling military reservation in Laur town, roughly four hours drive from the capital.

Construction tycoon Huang Rulun, China’s 49th richest with a net worth of $3.4 billion according to Forbes Magazine, led the donors and flew to the Philippines to grace the opening.

Huang described Duterte as an "irresistible force" fighting drug cartels, whom he said caused "great harm" to the world.

"Drugs wreck the country and bring ruin to the people. It is the common enemy of all mankind," he said in a speech.

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Huang has a “strong emotional connection” with the Philippines, having started as a small businessman in Manila’s Chinatown for five years before returning to China where he founded Century Golden Resources Corp., according to his company’s website.

Huang’s company operates 20 five-star hotels and 10 shopping malls in China. The privately-held firm, which employs 20,000 people, posted $5 billion in revenues last year.

The billionaire was seated across Duterte at a state banquet that Chinese President Xi Jinping threw in Beijing for the Philippine leader in October, a photo posted on the company’s website showed.

Duterte’s state visit to China signaled a thaw in relations that were strained by disputes in the South China Sea as he moved to shift the country’s allegiances away from the US.

Huang also met with several Filipino officials, including Speaker Pantaleon Alvarez, Energy Secretary Alfonso Cusi, and former Senator Ferdinand “Bongbong” Marcos Jr., according to the company website.

The President also thanked Kevin Andrew Tan, first vice president at Megaworld Corp., controlled by his father, Andrew Tan, the Philippines’ 10th richest man according to Forbes with a net worth of $2.5 billion.

Megaworld has made a mark in real estate with its urban “townships” that combine residential, office, leisure and recreational facilities in a single development.

Tan said funding for the rehabilitation facility was part of the company's corporate social responsibility.

"The objective itself is good. We need it," he told ABS-CBN News

Another donor, who was identified by the presidential palace only on Tuesday, is Jorge Consunji, president and chief operating officer of DM Consunji Inc.

DMCI has interests in construction, real estate, energy, water and mining.

A token was also reserved for construction solutions provider Frey-Fil Corp., whose high beams are a common sight in building sites across the country. -- with reports from Katrina Domingo, ABS-CBN News