Seoul, Jan 17 (IANS): North Korea fired an unidentified projectile toward the East Sea on Monday, South Korea's military said, in the recalcitrant regime's fourth show of force this year.

The Joint Chiefs of Staff (JCS) announced the launch in a text message sent to reporters. It did not elaborate, Yonhap news agency reported.

The latest launch came just three days after the North launched two suspected short-range ballistic missiles into the East Sea that it later claimed to be guided missiles fired by a railway-borne regiment during a firing drill.

Last week, the North warned of a "stronger and certain reaction" to the US' recent imposition of fresh sanctions on six North Koreans involved in the regime's weapons of mass destruction and ballistic missile programs.

The North also test-fired its self-proclaimed hypersonic missile on January 5 and on Tuesday last week, ratcheting up tensions amid an impasse in nuclear negotiations with the US.