(CNN) -- An unmanned drone crashed on a South Korean island near its disputed maritime border with the North, the country's defense ministry said Tuesday. The drone crashed on the Baekryeong Island on Monday afternoon, the ministry said -- soon after North and South Korean artillery batteries exchanged hundreds of shells across their western sea border. The South Korean military is investigating. The country's Yonhap news agency, quoting an unnamed government source, said the drone crashed near the western sea border, known as the Northern Limit Line after the artillery exchange -- raising the possibility that it was a North Korean reconnaissance plane.
The drone crashed on the Baekryeong Island on Monday afternoon . The two Koreas exchanged hundreds of shells across their western sea border .