June 12 (Reuters) - Three people were killed and five injured in an accident during equipment testing at a gas complex in Russia's Kingisepp district in the northern Leningrad region on Friday, Interfax news agency reported, citing local authorities.

The Kingisepp district is home to the Baltic Sea port of Ust-Luga, which has been a frequent target of Ukrainian attacks.

(Reporting by Maxim Rodionov; Editing by Aidan Lewis)