Chinese mainland authorities are demanding answers from Taiwan after a patrol boat from the island allegedly collided with a mainland fishing vessel, killing two fishermen in the waters off Kinmen, an island administered by Taiwan.

The fishing boat from the mainland was forcefully driven into waters near Kinmen by Taiwan authorities on Feb 14, causing all four people on board to fall into the sea, resulting in two fatalities.

The two surviving fishermen were rescued and returned to the mainland on Tuesday.

In an interview with Chinese State media, the fishermen described the incident, alleging that the Taiwan patrol boat had deliberately rammed their vessel.

Recalling the incident, one fishermen said they set out in the boat at around noon on Feb 14, and by 12:50 pm they saw a Taiwan coast guard boat heading toward them.

"There's no way our boat could have capsized on its own," he said. "Even if we made a sharp turn, it wouldn't capsize. It would take a collision to capsize, and we didn't expect the Taiwan vessel to come over and ram our boat, causing it to capsize. We dove into the water and only two out of four of us managed to get ashore.

"When fishermen from Taiwan come fishing near us, we treat them well. This time, we are deeply disappointed by how they treated us. I'm relieved that we are safe and returning to the mainland."

The incident has sparked outrage on the mainland, with many accusing the Taiwan authorities of using excessive force and failing to properly investigate the incident.

On Wednesday, Zhu Fenglian, spokeswoman for the Taiwan Affairs Office of the State Council, said that in initially attempting to downplay the events, responsible figures in Taiwan had insisted that their coast guard's actions were within the bounds of law enforcement.

"However, under mounting pressure from cross-Strait compatriots and the families of the deceased, Taiwan authorities reluctantly acknowledged that the capsizing of the mainland fishing boat and the resulting casualties were a direct consequence of a collision with a Taiwan coast guard vessel," she said.

Despite that admission, she said Taiwan authorities continued to deflect responsibility and obscure the truth behind the incident, using various excuses to evade accountability.

Zhu expressed strong condemnation for Taiwan's brutal treatment of mainland fishermen, emphasizing the blatant disregard for human life and the subsequent cover-up attempts.

She said the attempt to conceal the truth was not an isolated incident, citing a pattern of aggressive behavior toward mainland fishermen since the Democratic Progressive Party took office in Taiwan in May 2016.

Zhu called for Taiwan authorities to promptly disclose the true facts of the incident, hold those responsible to account, meet the reasonable demands of the victims' families, and issue a formal apology.

Stressing the gravity of the situation, Zhu reiterated the need to safeguard the legitimate rights of compatriots and vowed to prevent the recurrence of such incidents.