 They entered service in the 1950s and had been completely taken out of active service by the early 2000s and were transferred to law enforcement agencies.However, just like the Shantou, Beihai and Yulin classes that were transferred for law enforcement adaptation, these obsolete and aging boats are not satisfactory in their new roles due to their low maximum speed, sometime as low as 10 knots, which was not fast enough to catch the smugglers’ high speed motorboats.As a result, these boats were subsequently transferred again, this time to reserves, subordinated to naval militia in various Military Maritime Districts in China as training boats and port security / patrol boats within the confines of the harbors.