The U.S.S. Kyushu NCC-2344 was one of the original batch of sixty Okinawa-class frigates authorised for construction in 2273. Constructed from mid-2275 to early-2277 and commissioned shortly afterwards, the Kyushu was assigned to patrol Federation space behind the Klingon Neutral Zone.
On 20th February 2283 the monitoring probes in the Organian system fell silent. No contact could be established with the Organians themselves, but while this lack of response was considered typical for the Organians, combined with the silence of the probes some concerns were raised. The Kyushu under Lieutenant Commander Ses'ka'trel of Sauria was sent to the Organian system to determine what had happened.
On arrival on the 22nd of February the Kyushu discovered that the probes had apparently been simply "switched off" by unknown means, probably attributable to the Organians. In trying to contact the Organians themselves, and after no response to requests to approach the planet, the Kyushu risked doing so regardless and scanned Organia. They discovered that the Organians had left their world, leaving no trace even of the fabricated Richter Class D civilisation the crew of the Enterprise had encountered on their visit to the planet fifteen years earlier.
In the process of discovering this, the Kyushu encountered a Klingon E-4B Sek'leth-class escort apparently on its own mission to discover why their monitoring probe had gone silent. After a tense situation where they faced off against each other and leading to the Klingon successfully opening fire on the Kyushu, the Klingon commander decided that getting this information back to their High Command was of greater import than attempting to defeat the tactically superior Starfleet frigate.
Similarly, the Kyushu brought home the knowledge that the Organians had left with no warning and no indication of their ever returning, and had discarded their role as the galaxy's peacekeepers to the point that an exchange of fire could take place in orbit of their supposed homeworld.