After the Clone Wars, a droid led a Separatist holdout at the Citadel. However, the droid leading the garrison of battle droids was malfunctioning, and it was following its last directive from the finished war. It had adjusted its programming for a wider target range. The droid targeted all Force-sensitives, and it came to have a Force-sensitive child in the prison.
This is according to the RPG game Knights of Fate.