A resupply mission to a disputed shoal in the South China Sea was allegedly thwarted by a "military grade" laser beam, according to the Philippines.
The Filipino coast guard boat had to retreat because the laser's glare temporarily rendered the crew blind.
The ship was en route to a marooned navy ship that Manila has long used to assert its ownership of the Second Thomas Shoal.
In the past, China has used water cannons and sirens to impose its claim to a large portion of the South China Sea.
Only on Monday was the incident from January 6th made public. According to a statement from the Filipino coastguard, it was a "clear violation of Philippine sovereign rights" in the West Philippine Sea-designated waters.
The Chinese ship, in addition to twice flashing its laser lights, made "dangerous manoeuvres" at a distance of about 150 yards (137 meters) from the starboard side of the Filipino ship, according to authorities.
A representative for President Ferdinand Marcos Jr. declined to respond to questions from the BBC. Beijing didn't respond right away with a statement.
Beijing's broad claims in the South China Sea are unfounded historically, the UN's Permanent Court of Arbitration ruled in 2016.
One of the reasons why the Philippines brought the case was the tensions surrounding the shoal, which is known as Ayungin there.
The tribunal, which is also partially disputed by Vietnam, Malaysia, Brunei, and Taiwan, lacks the authority to put its decision into effect, and China has continued to erect massive structures over reefs in the waters.
Rodrigo Duterte, the former president of the Philippines, also refrained from disobeying the arbitration decision and instead worked to mend Manila's and Beijing's economic and political ties as he led his nation away from its longtime ally, the US.
But Mr. Marcos changed direction. His government gave the US permission to use four more military bases earlier this month.
The Philippine Daily Inquirer reported that in June of last year, a Chinese navy ship flashed blue lights and blinkers at a tugboat belonging to the Philippine coast guard.
That incident happened six months after Australia claimed China had targeted one of its warplanes off the northern coast of Australia with a military-grade laser.