This massive, crumbling shipwreck-turned-military station has become the latest flashpoint in tense US-China relations. Take a look inside.

• The Philippines turned a crumbling warship into a military outpost in the South China Sea. 
• The ship was deliberately run aground to reinforce their sovereignty claims in the region.
• China has repeatedly asked the Philippines to tow the ship away since it ran aground in 1999. 

A high seas scuffle between the Chinese and Philippine coast guards thousands of miles from the US mainland prompted the State Department to chastise China this week.

China, by "employing unsafe blocking maneuvers," had "interfered with the Philippines' lawful exercise of high seas freedom of navigation," US State Department spokesperson Matthew Miller said in a statement on Saturday.

The incident on Saturday involved a Chinese Coast Guard boat firing its water cannon at a Philippine vessel sailing through the South China Sea. The Philippine Coast Guard said the ship was carrying supplies to a Filipino military outpost.

The outpost in question? A massive, crumbling shipwreck that was repurposed by the Philippines and turned into a garrison in the South China Sea. 

In 1999, the Philippines deliberately ran the Sierra Madre, a World War II-era warship, aground on the disputed Second Thomas Shoal, also known as the Ren'ai Reef in China. The move was meant to reinforce the Philippines' sovereignty claims in the hotly contested South China Sea. 

According to the US Naval Magazine, the Sierra Madre was originally the USS LST-821, a tank landing ship built for service in World War II. It was later renamed the USS Harnett County, and used in the Vietnam War. The vessel was then transferred to the South Vietnamese before being given to the Philippines.

The Sierra Madre has since become a makeshift military outpost. A small group of troops now resides in the ramshackle vessel.

The remote assignment can be depressing and isolating for the troops stationed there. Joey Loresto, a staff sergeant, told The New York Times in 2013 that the outpost is "a lonely place."

Loresto told The Times that he preferred combat over being stationed on the Sierra Madre.  

The stranded vessel has also been a point of contention for China, which has since 1999 asked the Philippines to tow the boat away. 

And on Tuesday, a spokesperson for the Chinese Embassy in the Philippines defended the Chinese Coast Guard's use of its water cannons.

"Regrettably, in disregard of China's repeated dissuasion and warning, the Philippines tried to deliver the construction materials for overhauling and reinforcing the 'grounded' military vessel," the Chinese spokesperson said in a statement on Tuesday. "This is the cause of what happened there this time."

"Under such circumstances, the Chinese side was made to respond with necessary moves. China Coast Guard took warning law enforcement measures in accordance with the law," the spokesperson added.

Commodore Jay Tarriela, a spokesperson for the Philippine Coast Guard, said on Sunday that the Philippine Coast Guard "strongly condemns" the Chinese Coast Guard's "dangerous maneuvers and illegal use of water cannons," adding that they were a violation of international law.  

Although the US has no territorial claims in the South China Sea, it has carried out regular naval operations in the region.

"The United States is defending every nation's right to fly, sail, and operate wherever international law allows, as USS Benfold did this week. Nothing PRC says otherwise will deter us," the US Navy said in a statement on January 20, 2022, when it conducted a freedom-of-navigation operation in the South China Sea.