The USS Kelso was a Federation starship. On stardate 72487.91 (in 2395), the vessel was destroyed. A subsequent investigation by the crew of the USS April revealed that the Kelso was testing a cloaking device instead of participating in its "official" mission (investigating effects of the Hobus supernova on the Devron sector's star systems).
The initial belief was that the ship was destroyed in an attack. The investigation revealed that a coolant leak led to venting plasma, which in turn reacted explosively was ionizing radiation in the space near the ship. (ST website: The Path to 2409)