Seoul, North Korea fired an artillery shot into the Yellow Sea earlier this week, presumably from a multiple rocket launcher, a defence source said here in Wednesday, as the US has deployed six F-35A stealth fighters on the peninsula for combined drills.

The South Korean military had detected a single trajectory believed to be an artillery shot on Monday morning, the source said without providing additional details, including where it was fired, Yonhap news agency reported.

On Sunday, North Korea fired two suspected artillery shots from multiple rocket launchers.