MANILA—Satellite images contradict China's claim that its vessel was "suddenly besieged by 7 or 8 Filipino fishing boats" near Reed Bank on June 9, a maritime law expert said Saturday.

Professor Jay Batongbacal, director of the UP Institute for Maritime Affairs and Law of the Sea, said the visible infrared imaging radiometer suite (VIIRS) data on the night of the incident "shows only a few fishing vessels operating in the area of Reed Bank at the time."

"Each boat-icon is a fishing vessel identified by its bright lights. They are spread over the wide area of Reed Bank; the closest two lights are about 3-5 nautical miles (approx. 7 to 9 km) apart. What 7-8 vessel swarm of night-marauding Filipino fishing boats is China talking about?" he said in a Facebook post.

Batongbacal also shared another Facebook post showing the satellite image of the site of the incident.

China on Friday said Chinese fishing boat Yuemaobinyu 42212 was berthed near Reed Bank when it was swarmed by Filipino fishing boats.

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"During evacuation, 42212 failed to shun a Filipino fishing boat and its steel cable on the lightning grid of larboard bumped into the Filipino pilothouse. The Filipino fishing boat tilted and its stern foundered," Beijing said.

These fishing boats hindered the Chinese ship captain's attempt to rescue the fishermen of the Filipino boat that sank, it added.

Batongbacal earlier expressed doubt that the "collision" was an accident, saying a moving vessel would not collide with an anchored vessel in the open ocean and endanger the safety of those on board.

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