By Islamuddin Sajid 

ANKARA (AA) - South Korea on Friday imposed sanctions on 15 North Korean individuals and 16 institutions in response to recent missile tests and drills by tactical nuclear operation units.

This is for the first time Seoul has announced its unilateral sanctions against Pyongyang since 2017, Yonhap News Agency reported.

South Korea has blacklisted officials from shipping companies, the North's missile program, and those involved in the procurement of weapons of mass destruction.

"We strongly condemn North Korea for staging a series of missile provocations with unprecedented frequency recently and suggesting the use of tactical nukes against us," the agency said, citing a Foreign Ministry statement.

The announcement came hours after North Korea fired another short-range ballistic missile (SRBM) into the East Sea at 1:49 a.m. Friday (1649GMT Thursday) and fired 170 artillery shots into maritime “buffer zones.”

President Yoon Suk-yeol also called North Korea's latest pre-dawn missile launch and artillery fire into "buffer zones" a violation of the 2018 agreement.

Yoon was referring to the 2018 agreement between the two countries, which created buffer zones along land and sea boundaries and no-fly zones above the border.

However, the North Korean military said the latest missile launch and artillery fire were in response to South Korea's “provocative action.”

"South Korean army conducted artillery fire for about 10 hours near the forward defense area of the KPA Fifth Corps on Oct. 13, taking serious note of this provocative action by the south Korean military in the frontline area, we took strong military countermeasures," a spokesman for the General Staff of the Korean People's Army said in a statement.

On Wednesday, Pyongyang also fired two long-range strategic cruise missiles, involving units operating "tactical nukes, according to the state-run Korean Central News Agency.

On Oct. 4, the US and South Korean forces held live-fire joint drills after North Korea fired a missile that flew over Japan, the first such instance in five years.

Tensions on the peninsula rose in 2020 when North Korea attacked and blew up the inter-Korean liaison office along the border. Seoul has threatened a strong response if Pyongyang "further worsens the situation."

However, tensions soared further recently after Seoul and Washington held joint military drills.