BEIJING - Chinese Vice-Foreign Minister Cheng Guoping on Thursday expressed strong dissatisfaction with Russia over an alleged attack on a Chinese fishing vessel, which has left a fisherman missing.

China is very dissatisfied with Russia's actions to detain the Chinese fishing boat and crew after opening fire on the boat, Cheng said in a statement when summoning a Russian diplomat.

China demands Russia to thoroughly investigate the incident and inform China of the results in a timely manner, Cheng said.

Russia should make sure that the detained sailors are safe, their legitimate rights are guaranteed and they are granted with humanitarian treatment, Cheng said.

Earlier media reports said Russia also detained another Chinese fishing boat one day before the attack which occurred on Monday.

Cheng also demanded Russia to release the boats and let the fishermen go quickly and make all-out efforts to search for the missing sailor.

The Russian diplomat said Russia is investigating the incident, and will notify China as early as possible. He said he will report China's stance back to Russia.

According to the Chinese Consulate in Vladivostok, Russia's Far-East region, two Chinese fishing ships from China's eastern Shandong province were seized by Russia--one on Sunday and the other, on Monday.

One ship carried 19 fishermen while the other had 17 on board. One ship was detained at the port of Nakhodka, while the other was heading there.

The local coastal service notified the consulate on Tuesday that the two ships were detained because they entered Russia's exclusive economic zone.

According to the RIA Novosti news agency, a Russian coast guard vessel, the Dzerzhinsky, fired warning shots and then opened targeted fire to stop a Chinese fishing ship that had been fishing for squid.

None of the Chinese fishermen were killed or wounded during the incident, RIA said.