ULUGAN BAY, Philippines – First ashore were a group of scouts, swimming slowly and silently to the beach, gauging the defenses before calling in the main body of 84 U.S. and Philippine Marines.

It was all stealth – at least until they were surrounded by camera-wielding journalists.

"Will the media please stay in a group to one side," came the plea through loud speakers from the sort of master-of-ceremonies from the Philippines military.

"This would normally be taking place at night," he informed us. "And they would be wearing night-goggles," he continued. "Please will the media stay to one side."

Ian Williams /NBC News

U.S. and Philippine Marines participate in a joint exercise in Ulugan Bay, Philippines on Wednesday.

The main body of Marines swept in, crouching in their inflatables, guns at the ready. But the journalists were equally well prepared. The Philippines media is nothing if not feisty, and completely ignored the increasingly forlorn voice on the loud speaker. They were immediately at the side of the Marines as, through a fog of fake smoke grenades, they launched an assault on a compound that had been taken over by "terrorists.”

"Will the media please group to one side,” the refrain continued. Thank goodness the troops were firing blanks.

Playing down China’s fears
These exercises are an annual event, and Wednesday's drill was the culmination of two weeks of exercises that have involved 4,500 U.S. soldiers and 2,500 from the Philippines.

It comes at a time of rising tension in the energy-rich South China Sea, ownership of which is disputed by China (which claims just about all of it), as well as the Philippines, Vietnam, Brunei, Malaysia and Taiwan.  

Beijing has been increasingly assertive in the area, and the U.S.-Philippine drill coincides with a tense stand-off between Chinese and Philippine vessels around Scarborough Shoal in a different part of the South China Sea.

Beijing has condemned the current exercises, saying it raises the risk of confrontation. But U.S. officials Wednesday were keen to play down the China angle, insisting the exercises were all routine.

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US and Philippine Marines participate in a joint exercise in Ulugan Bay, Philippines on Wednesday.

"[The joint-exercises] been taking place for decades," Ensign Bryan Mitchell, the US. Marine spokesman, told me.

"The planning took place months and months ago. There are a whole range of real world applications." Much of this year's exercises have been geared towards humanitarian relief, he added.

"For us this exercise is all about achieving inter-operability, and we are not allowing any of the other things going on to let us lose focus on that."

The purpose of the exercise was a little more blurred for Neil Estrella, a spokesman for the Philippine forces. An exuberant man in dark glasses, he waved his arms towards the South China Sea in front of him.

"China, they claim it all," he said with a sharp distaining laugh. "They'll be claiming America next."

I asked him about the scenario of Wednesday's exercise, re-taking a coastal base from "terrorists."

There was another disdainful laugh as he shifted his glasses. "This could just as easily be an island," he said. "We call them terrorists – but it’s a generic term."

As we spoke, loud pops and bangs punctuated the conversation as the Marines continued to clear the buildings behind us, and the increasingly exasperated voice on the loud speaker urged: "Will the media PLEASE keep to one side."

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