Ming Shilu
Several Malay envoys from the [[Malacca sultanate]] were attacked and captured in 1469 by Vietnamese navy as they were returning to Malacca from China. The Vietnamese enslaved and castrated the young from among the captured. A 1472 entry in the [[Ming Shilu]] reported that some Chinese from [[Nanhai District|Nanhai]] escaped back to China after their ship had been blown off course into Vietnam, where they had been forced to serve as soldiers in Vietnam's military. The escapees also reported that up to 100 Chinese men remained captives in Vietnam after they were caught and castrated by the Vietnamese after their ships were blown off course into Vietnam. The Chinese Ministry of Revenue responded by ordering Chinese civilians and soldiers to stop going abroad to foreign countries. China's relations with Vietnam during this period were marked by the punishment of prisoners by castration.