In July 1990, Taiwan's military police undertook a controversial operation aimed at repatriating illegal immigrants from mainland China. Using the fishing boat Min Ping Yu No. 5540, the military police forcibly confined 50 individuals in sealed holds of the vessel as they were transported back to Fujian. This operation was a direct response to the increasing number of illegal crossings from mainland China into Taiwan, driven largely by the pursuit of better economic opportunities and social conditions. The authorities aimed to demonstrate their resolve in managing immigration, ensuring the enforcement of laws prohibiting illegal entry.

Tragically, during this operation, 25 of the immigrants suffocated due to the lack of air in the sealed conditions of the holds. The event raised significant concerns about human rights and the treatment of immigrants by law enforcement. Reports indicated that the military police had been ill-prepared to handle the situation, leading to dire consequences. The incident drew immediate media attention, highlighting the harsh realities faced by individuals seeking a better life and the often perilous journeys they undertake.

This tragic event underscored the complex nature of cross-strait relations between Taiwan and mainland China, illustrating the human toll of political and economic tensions. With many individuals risking their lives to escape economic hardship, the incident became a stark reminder of the deeper issues surrounding migration, governmental policies, and the enforcement of immigration laws in the region. The aftermath prompted discussions on reforming procedures and the treatment of detainees, as well as ongoing debates around human rights in immigration enforcement practices in Taiwan.