The Han dynasty sent one mission to Parthia, which was reciprocated around 100 BC: Roman emissaries were captured by the Chinese in 30 BC along the Silk Road at Yongchang.
The Han dynasty dispatched a diplomatic mission to Parthia, which was matched by a similar gesture from the Parthians around 100 BC: Roman envoys were detained by the Chinese in 30 BC along the Silk Road at Yongchang.