A 6.8 magnitude aftershock struck off Russia's Kamchatka Peninsula in the Pacific Ocean on Sunday, the regional branch of the Ministry of Emergency Situations announced on social media.

The quake, which occurred at 17:37 local time (0537 GMT), was 277 km from Petropavlovsk-Kamchatsky, the regional capital, at a depth of 26 km.

According to the Kamchatka Tsunami Warning and Monitoring Center, tsunami waves generated by the quake are not expected to exceed 19 cm.