It has become the norm that each time a new representative of the secessionist-minded Democratic Progressive Party is about to take office as head of the authorities on Taiwan island, some moves are made to test the Chinese mainland's bottom line.

This year it led to tragedy. Two fishermen from Fujian province drowned when their boat capsized after being bumped by a vessel of the Taiwan authorities which was chasing it from waters near Kinmen Island, which the latter claimed were "restricted" waters.

As a spokesperson of the Taiwan Affairs Office of the State Council made clear, "Fishermen on both sides of the Taiwan Strait have been operating in traditional fishing grounds in the Xiamen-Kinmen maritime area since ancient times, and there is no such thing as 'prohibited or restricted waters'."

This was the first provocation by the DPP authorities ahead of the independence-minded Lai Ching-te taking office as head of the Taiwan authorities on May 20. How the DPP authorities handle the incident will likely set the tone for cross-Strait interaction after Lai takes office.

As DPP chairman, Lai, on Wednesday, called for properly handling the aftermath of the tragedy, resolutely enforcing the law, and preventing similar incidents from happening in the future. This may sound consistent with his vow of prudence in handling cross-Strait relations and desire for stable cross-Strait relations. But how the incident is actually handled by the DPP authorities will be the touchstone for the sincerity of such remarks.

To the bereaved families, the loss of their loved ones was doubly tragic as it occurred during the Spring Festival holiday, a traditional occasion for family reunions. Meanwhile, it cannot but inspire popular indignation that the DPP authorities did not acknowledge "multiple contacts" between their vessel and the boat from the mainland until a week afterward. The maritime law enforcement authorities of Taiwan have been abusive and dishonest.

A mainland delegation led by the Taiwan Affairs Office of Quanzhou, Fujian province, is now in Kinmen to investigate the case. Hopefully, the local Kinmen authorities will fully support the investigation and make sure the matter is properly resolved, so that any similar tragedy can be prevented from happening. The Taiwan Affairs Office of the State Council has called for a clear explanation of what happened.

The incident has once again raised concerns about the legitimacy of the DPP authorities' "law enforcement" actions in the waters, which excessively target mainland fishing vessels. With the mainland authorities having instigated patrols and inspections in the area in response to the tragedy, it is foreseeable that these will be regularized in the waters around Kinmen and other islets in the Taiwan Strait so as to maintain law and order.