By Kristin Broughton
The U.S. on Friday imposed sanctions on a number of Russian individuals and firms in response to a November attack off the coast of Crimea and the annexation of the Ukrainian peninsula five years ago.
The sanctions were imposed in conjunction with the European Union and Canada, which took similar actions Friday, the U.S. Treasury Department said.
"The United States and our transatlantic partners will not allow Russia's continued aggression against Ukraine to go unchecked," Treasury Secretary Steven Mnuchin said in a statement.
The sanctions, imposed by the Office of Foreign Assets Control, follow a standoff late last year, in which Russian coast guard forces opened fire on and seized three Ukrainian ships in the Kerch Strait.
OFAC placed sanctions on four Russian officials, all members of the country's Federal Security Service, who U.S. officials said were involved in the attack. They are Gennadiy Medvedev, a deputy director of the Border Guard Service; Sergey Stankevich, head of the Border Directorate ; Andrey Shein, deputy head of the Border Directorate; and Ruslan Romashkin, head of the Service Command Point.
Additionally, the agency placed sanctions on two Ukrainian separatists involved in organizing elections in the country's volatile Donetsk region: Aleksey Alekseevich Naydenko and Vladimir Yurievich Vysotsky.
OFAC also named six Russian defense firms, which the agency accused of misappropriating Ukrainian state assets to provide services to the Russian military. They are Yaroslavsky Shipbuilding Plant, a state-owned shipbuilding plant; Zelenodolsk Shipyard Plant, a ship manufacturer; AO Kontsern Okeanpribor, a producer of hydroacoustic equipment; PAO Zvezda, a diesel engine supplier; AO Zavod Fiolent, an electronics manufacturer; and GUP RK KTB Sudokompozit, a defense producer.
Two other firms were named in the announcement: LLC SK Consol-Stroi LTD, one of Crimea's largest construction companies, and LLC Novye Proekty, to which Russian authorities in 2016 awarded an oil and gas exploration license for the Crimean Black Sea shelf, according to the release.
A message seeking comment from the Russian Embassy in Washington wasn't immediately returned late Friday.
Write to Kristin Broughton at Kristin.Broughton@wsj.com