Turkish police arrested six suspected Daesh militants, including a Japanese national, in the southeastern province of Gaziantep on Wednesday.
Five people - non-Turkish - were arrested near the border as they tried to cross into the war-torn country, a security source said on condition of anonymity.
Separately, a 24-year-old Japanese citizen, only known by his initials M.M, was arrested at a police checkpoint near the Turkish-Syria border, security sources said.
Police determined that the Japanese national has been in touch with a known Daesh militant inside Syria through social media.
According to security officials, the radical militant convinced him to join the terrorist organization.
Officials said the Japanese person would be deported.