Ukrainian officials say an explosion occurred in the southern city of Odesa near a political party's office.
An Interior Ministry spokesman in Odesa said on March 12 that the blast at the Admiraltesky business center has been classified as a terrorist attack.
No one was injured in the blast, which occurred early on March 12.
The political party Samopomich (Self-Reliance), which is part of Prime Minister Arseniy Yatsenyuk's government, has an office in the business center.
The facade of the building and the party office were damaged by the explosion.
The blast is the latest in a series of blasts in Odesa that began in December, all at buildings that house organizations aiding those fighting Russian-backed separatists in eastern Ukraine.
There have been similar blasts in Kharkiv, a large eastern city under government control.
An explosion at the Odesa office of the nationalist organization Right Sector occurred on March 5.
