Taiwan's military has conducted a naval drill in waters between Taiwan and the Philippines, close to the spot where Filipino coast guard personnel opened fire on a Taiwanese fishing vessel last week, killing a 65-year-old-crew member.
Several vessels, including two missile boats as well as jet fighters, took part in the drill on Thursday, underscoring Taiwan's anger over the incident, which has dominated local media coverage for the past week.
On Thursday, the Philippines issued a second apology to the Taiwanese government for the deadly incident, Al Jazeera's Marga Ortigas, reporting from Manila, said.
In a meeting with Taiwan's foreign ministry, Amadeo Perez, a special representative of Philippine President Benigno Aquino III, said he was conveying "the Filipino people’s deep regret and apology over the unfortunate and unintended loss of life" following the May 9 incident.
Perez also said that the Philippine government is ready "to give financial assistance to the family" of the dead fisherman.
The Philippines' has no formal diplomatic ties with Taiwan because of it's "One China" policy, which only recognises the People's Republic of China as the sole legitimate government.
China does not recognise Taiwan's independence, and considers it as one of its provinces.
Taiwanese Premier Jiang Yi-Huah, however, brushed aside the apology by Manila, the second in 24 hours, as insufficient and insincere.
As a result, a series of Taiwanese sanctions imposed on the Philippines, including a hiring freeze placed on Philippine workers coming to Taiwan, the recall of Taiwan's semi-official to Manila, and the discouraging of Taiwanese travel to the Southeast Asian nation, will all remain in effect.
Confrontation at sea
The circumstances behind the May 9 shooting remain shrouded in controversy.
While the Philippines acknowledges that its coast guard personnel did open fire on the Taiwanese boat, it said the action was taken in self-defence to prevent the Taiwanese from ramming their own vessel.
Ortigas noted that in the second letter of apology, the Philippines did not use the word "to compensate" the victim, as it would have meant "an admission of guilt".
She also said that the Philippines has insisted that the Taiwanese fishing vessel has "trespassed" Philippine waters.
The incident took place in waters southeast of Taiwan, and north of the Philippines, in a location considered by both to be well within their 200 nautical mile-from-shore exclusive economic zones.
Ortigas said that there was "outrage" in Manila that Taiwan had rejected the second apology.
Fourteen Taiwanese police investigators arrived in Manila on Thursday to take part in a Philippine inquiry ijto the affair.
The continuing tensions between Taipei and Manila have placed the US in a bind, as the two are both allies of Washington in the Asia-Pacific region.
"We want them to work through their differences on this issue as expeditiously as they can," Patrick Ventrell, US State Department spokesman, told reporters.
China is also closely monitoring the upsurge in tensions, doing its best to make common cause with Taipei on a sensitive issue of maritime sovereignty.
Beijing sees the affair as a good opportunity to emphasise its claims over Taiwan, from which it split amid civil war in 1949.
Taiwan has so far resisted China's efforts to mount a joint front against Manila.