SEOUL (Reuters) — North Korea said on Monday it had found two female journalists from the United States guilty of entering the state illegally and sentenced both to 12 years of hard labor, a step likely to compound diplomatic strains with Washington and regional powers.

The female journalists, Euna Lee and Laura Ling of US media outlet Current TV, were arrested on March 17 while working on a story near the border between North Korea and China.

"The trial confirmed the grave crime they committed against the Korean nation and their illegal border crossing as they had already been indicted and sentenced each of them to 12 years of reform through labor," the official KCNA news agency said in a brief dispatch.