N Korea 'shells near South warship'

North Korea has fired shells into disputed waters near a South Korean warship, South Korean media report.

The Yeonpyeong island near the disputed western sea border incident took place , Yonhap news agency said .
Tuesday across the border to South Korea North Korean ships at sea fired three warning . The answer will retaliate .
In 2010 , Yeonpyeong North Korean shelling killed four people .
Event 18:00 local time (09:00 GMT) later , the report said , citing South Korean officials .
" Shell fell near our ship was on routine patrol in our area , but it did not cause any damage to our ship , " the South Korean Ministry of Defense Agency spokesman - France-Presse news agency reported the .
Local television network YTN Yeonpyeong residents reported being taken from bomb shelters .
Regular long the two Koreas , conduct exercises near the western sea border between the two countries was at an extreme point .
The Korean War UN boundary , but is not recognized in North Korea after.
In March traded artillery fire across the border .
The South Korean military exercises in response to North Korea on Yeonpyeong island , killing two marines and two civilians in 2010 said opened fire .
Earlier that year , a South Korean warship sank near the island of Baengnyeong dead 46 people were leaving . Seoul says Pyongyang torpedoed ship , but North Korea denies any role in the incident .