Taiwan is calling on the Philippines to explain and apologize for the reported firing of a Philippine government boat on a Taiwanese vessel on Thursday that resulted to the death of one fisherman.

According to Taipei news sources, four people were aboard the Taiwanese vessel when it was fired on. The boat was said to be navigating within disputed waters when the incident happened.

In an official statement, Taiwan's Foreign Minister David Lin condemned the incident "strongly" and said that a full investigation must be opened by the Philippine government.

The reported firing, which killed 65-year old Hung Shih Cheng, happened in waters 170 miles south of Taiwan, Taipei said.

Response vessels have already been sent to the area by Taiwan's coast guard to aid the fishermen.

When asked for a statement, the Philippine Navy denied any hand in the firing incident.

In the formal statement released by the Philippine Navy, they said there was no presence of their ships in the area when the reported incident happened.

"The Philippine Navy denies any involvement in... an incident where a Taiwanese fisherman was reportedly shot and the wound led to his death," the statement said.

The AFP News Agency has reported that Albert del Rosario, Philippine Foreign Secretary, could also not corroborate Taiwan's claims. "We will check that," del Rosario was quoted to have said.

According to the Associated Press, a news conference is set to be held by the Philippine coastguard, a separate entity.

In the past, there had been several instances of Taiwanese fishermen being apprehended in the area and detained by Philippine authorities, but there had been no reports of shootings, according to BBC correspondent Cindy Sui in Taipei.

Territorial disputes have been escalating in the region in recent months with China, Taiwan, Philippines, Malaysia, Bruinei and Vietnam presenting overlapping claims over the South China Sea.

These conflicts have been long-standing but China's more aggressive stance in recent months has led to increased tension with its regional neighbours.

Last year, China and the Philippines also engaged in a prolonged standoff over the Scarborough Shoal to which both countries are laying claims. The impasse ended after some time but not without straining the ties between the two countries.