Roilo Golez at the forum, Upholding the Law of the Sea Convention and the Post-Arbitration Philippine Challenge, on July 15, 2016, at the Malcolm Theater, UP College of Law, Diliman, Quezon City. Fernando G. Sepe Jr., ABS-CBN News

MANILA - (3rd UPDATE) Former national security adviser Roilo Golez passed away on Monday. He was 71.

His son Parañaque Vice Mayor Rico Golez confirmed the news to radio DZMM.

The late statesman died of a heart attack, House Majority Leader Rodolfo Fariñas said.

"It is with sadness that I post here that Danny Suarez just called me with the information that our former colleague, ROILO 'ROY' GOLEZ, passed away due to heart attack," the Ilocos Norte congressman said in a statement.

Golez was a fierce advocate of the Philippines' rights to the West Philippine Sea. He was scheduled for an interview on Manila's maritime row with Beijing over ANC early Monday, but he felt unwell.

A graduate of the US Naval Academy, Golez was a former Philippine Navy officer.

After his military stint, he served as postmaster general under then President Ferdinand Marcos. He later withdrew support for the Marcos regime and joined protests that eventually overthrew the dictatorship.

He was a Congress representative of Parañaque for 6 non-consecutive terms from 1992 to 2001.

He served as former president Gloria Macapagal-Arroyo's security adviser from 2001 to 2004.

Golez was also a professor at the Asian Institute of Management and the University of the Philippines-Diliman, where he studied Masters in Business Administration, graduating as class valedictorian.

He was also an active member of the Philippine Red Cross, Boy Scouts of the Philippines, Rotary International and several health organizations.

Golez was a huge loss to the defense of the country's territorial sovereignty, said Magdalo Rep. Gary Alejano.

"Hindi rin siya pumayag na lapastagan tayo ang ating karapatan sa West Philippine Sea kaya malaking kawalan po ang pagkamatay ni Sec. Golez," he said.

(He did not allow our rights to the West Philippine Sea to be trampled. Sec. Golez's death was a huge loss.)

Other lawmakers took to social media to mourn Golez's passing.

Roilo Golez, the Naval Officer. My snappiest salute, sir. You served the country well, living life like a true soldier—fighting for the country as a last act. — Ruffy Biazon (@ruffybiazon) June 11, 2018

My sincerest condolences to the family and loved ones of my former colleague Sec. Roilo Golez. He was a true statesman who will be sorely missed especially during these trying times in our country’s history. — Chiz Escudero (@SayChiz) June 11, 2018

Very surprised and saddened to hear of Cong @roilogolez ‘s passing. Condolences to vmayor @ricogolez and family. Was a highly respected member of the House. RIP Manong Roy 🙏🏽 — Sonny Angara (@sonnyangara) June 11, 2018

With my deepest sympathies VM @ricogolez on Cong. Roy’s passing. — JV Ejercito (@jvejercito) June 11, 2018