MANILA -- (UPDATED) Red banners with the words "Welcome to the Philippines, Province of China" were hung on several pedestrian overpasses in the capital on Thursday, the second anniversary of the Philippines' win over China in an international arbitration court.

The message was written in both English and Mandarin. The banners had a similar design and also bore the Chinese flag. It was not immediately clear who installed the signs.

Ronald Gustilo posted a photo of one of the banners, which he said was hung on the pedestrian overpass in Philcoa, Quezon City.

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"Anong kalokohan ito?" Gustilo captioned his Facebook post.

Similar banners were spotted on footbridges on Quezon Avenue in Quezon City, on the southbound lane of C5, and near the Ninoy Aquino International Airport in Pasay City.

One of the banners was hung along Quezon Avenue in Quezon City. Photo by: Johnson Manabat, ABS-CBN News

One of the banners was hung along Quezon Avenue in Quezon City. Photo by: Mark Demayo, ABS-CBN News

One of the banners was hung along Quezon Avenue in Quezon City. Photo by: Mark Demayo, ABS-CBN News

A tarpaulin that says the Philippines is a province of China was seen along the south bound lane of C5. Photo courtesy: Tasha Tuazon

Another banner was seen on a pedestrian overpass near the Ninoy Aquino International Airport in Pasay City. Photo courtesy: Ryan Pontejos

Former Solicitor General Florin Hilbay posted a photo of another of the tarpaulin and asked the government agencies to take down the banner that has sparked negative comments.

"Not funny. On this day, July 12, we commemorate our victory in Philippines v China," said Hilbay, who led the Philippines' legal panel that protested China's sweeping claims in the South China Sea before the Permanent Court of Arbitration.

In a decision released on July 12, 2016, the Hague-based tribunal "found that China had violated the Philippines’ sovereign rights in its exclusive economic zone" after the Asian giant interfered with Philippine fishing and oil exploration in the area, constructed artificial islands and allowed Chinese fishermen to fishing in the zone.

President Rodrigo Duterte refused to flaunt the decision as he sought closer ties with Beijing, while turning away from Manila's traditional ally Washington.

Asked for comment, Presidential spokesperson Harry Roque said the installation of the banners was "absurd."

"I'm sure it's the enemies of the government that's behind it. So to them, try again. You need a better gimmick than that," he said in a press briefing.

"We assure the public on the second year anniversary that we will continue to assert what is ours while we move on with our bilateral relations with China," Roque added.

Duterte's predecessor, Benigno "Noynoy" Aquino III initiated the arbitration case but the court handed down its verdict less than a month after the incumbent took over.

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