North Korea says American professor Tony Kim held for 'hostile' acts

North Korea has confirmed the arrest of a US professor for alleged acts of hostility aimed at overthrowing the country's regime.

The Korean Central News Agency said Tony Kim, also known as Kim Sang Dok, was "intercepted" at Pyongyang's airport on 22 April as he tried to leave the country.

In the North's first confirmation of the professor's detention, the agency said he had been held for "committing hostile criminal acts aimed to subvert the country".

He is the third American being detained in North Korea.

His arrest is likely to add to tensions between North Korea and the United States.

As Washington deals with North Korea and its nuclear weapons programme, President Donald Trump has said all options, including military action, are on the table.

But the US leader also said this week he would be "honoured" to meet North Korean leader Kim Jong-Un under the right conditions.

The detained professor had been teaching accounting at the Pyongyang University of Science and Technology, which reported last month he had been held and said the arrest was not connected to the school's work.

It added that the Swedish embassy in Pyongyang, which handles issues involving US citizens as Washington has no diplomatic ties with the North, was "actively involved" in talks.

Mr Kim is a former professor at Yanbian University of Science and Technology in China, close to the Korean border.

South Korea's Yonhap news agency said Mr Kim is 55 and had been involved in relief activities for children in rural area of North Korea. It described him as a "religiously devoted man".

Two other US citizens were sentenced last year to lengthy prison terms in the North.

Korean-American pastor Kim Dong-Chul was sentenced to 10 years of hard labour for "spying".

College student Otto Warmbier was sentenced to 15 years for stealing a propaganda material and for "crimes against the state".

North Korea has arrested and jailed several US citizens in the past decade, often releasing them after high-profile visits by current or former US officials or former US presidents.