Ukraine's security service said it has detained several people accused of plotting to declare a separatist "people's republic" in Odessa on the Black Sea, similarly to rebel territories in Ukraine's east.
Security officers seized explosives and weapons from members of the alleged rebel group, the SBU said Monday on its website.
The security service also claimed that the alleged separatist group was headed by a Russian citizen, whom the statement identified only by his last name, Stepanov, and was "created and funded by Russian secret services."
Odessa, a Black Sea port city with a substantial Russian-speaking population, was the site of deadly clashes between pro-Moscow and pro-European activists this spring. More than 40 people were killed during the violence, most of whom were caught in a building that was set on fire.
Since then the city, renowned across the former Soviet Union for its ethnic mix and a wry sense of humor, has remained largely peaceful.