Taiwan conducted military exercises in the sea north of the Philippines Thursday, raising tensions between the two sides to the highest level since a Taiwan fisherman was shot by Filipino coastguards last week, dpa reported. Four armed Taiwanese coastguard vessels participated in the manoeuvres, going as far as 174 nautical miles (322 kilometres) from the southern tip of Taiwan, coastguard spokesman Shih Yi-Che said. A spokesman for Taiwan's defence ministry said three warships, two fighter aircraft, and several radar aircraft and military helicopters were supporting the coastguard in the exercises. The naval manoeuvres are part of a second round of punitive actions that Taiwan took against the Philippines Wednesday evening. These actions included the freezing of all economic and cultural exchanges, as well as a "red" travel warning to its citizens to refrain from travelling to the Philippines. Taiwan had already suspended the issuing of work visas to Filipino workers, and expelled the Philippine representative in Taiwan. A special envoy sent by Manila to de-escalate the crisis was also expelled. In what he called an "exit statement" Thursday, envoy Amadeo Perez reiterated the Philippines' "deep regret and apology" for the death of the Taiwanese fisherman, and offered to give financial assistance to his family. Perez, chairman of the Manila Economic and Cultural Office, said he told Ministry of Foreign Affairs Director General Benjamin Ho that the Philippine government had started an investigation into the incident. Taiwan says the Philippine authorities have shown "little sincerity" in their handling of the shooting. Fisherman Hung Shih-cheng, 65, died Thursday after the Philippine coastguard fired on his boat 164 nautical miles south of Taiwan. Taipei says he died after being shot in the neck.