North Korea has arrested a U.S. tourist for "hostile activities", Pyongyang's state media said Friday, bringing the total number of Americans held by the reclusive regime to three.

The official Korean Central News Agency (KCNA) said the man was being questioned, identifying him only in Korean without providing the English spelling of his name.

The EU said Wednesday it was "deeply concerned" about the threat of a new nuclear test by North Korea, amid stepped-up activity at one of its main test sites.

"The EU is deeply concerned about reports that the DPRK (Democratic People's Republic of Korea) may be preparing the fourth nuclear test," EU states said in a joint statement to a meeting of the UN watchdog IAEA's board of governors in Vienna. 

Syrians voted as fighting raged Tuesday in a presidential election in which Bashar Assad is looking to tighten his grip as his forces battle rebels in a devastating three-year war.

In the afternoon, the higher electoral commission extended voting by five hours "due to heavy turnout."

Prime Minister Shinzo Abe may visit North Korea, Japan said Tuesday, days after announcing a deal to re-open the probe into Japanese citizens kidnapped by spies in the Cold War.

Any such visit would be controversial, especially in Seoul and Washington, which have led the charge to further isolate Pyongyang over its ballistic missile and nuclear programs.

South Korea on Tuesday repatriated a North Korean fisherman but rejected Pyongyang's demands to return two others picked up by the coastguard at the weekend.

Seoul's Unification Ministry said the repatriation took place at the border truce village of Panmunjom.

South Korea rejected North Korea's request Monday to send home all three of its citizens who were found adrift last week in a small boat across their sea border, officials said.

The boat with three North Korean men on board was spotted by a South Korean coastguard vessel on Saturday off the South's east coast and the men questioned by security officials, Seoul's unification ministry said.

South Korea urged North Korea Sunday to release a Seoul missionary sentenced to hard labor for life for allegedly spying and operating an underground church, calling his sentence "deeply regrettable". 

Kim Jeong-Wook -- captured in the North last October -- faced an array of charges including illegally entering the country, spying for Seoul's intelligence agency, running an underground church and other "anti-state propaganda and agitation", according to the North's official KCNA news agency.

North Korea sentenced a South Korean missionary to hard labor for life after accusing him of espionage and setting up an underground church, state media said Saturday, the latest Christian preacher to run into trouble in the secretive state.

Prosecutors had sought a death sentence for Kim Jeong-Wook, identified by the North's official news agency KCNA as Kim Jong Uk, during Friday's trial.

South Korea gave a guarded response Friday to a Japanese deal to ease sanctions against North Korea, stressing the need to maintain a united front against Pyongyang's nuclear weapons program.

Japanese Prime Minister Shinzo Abe announced Thursday that Tokyo would relax some sanctions if North Korea delivers on a pledge to reinvestigate the cases of Japanese nationals kidnapped to train spies.

Japan said Thursday it would ease sanctions against North Korea after the secretive state agreed to reinvestigate the kidnapping of Japanese nationals to train spies, in a significant breakthrough for testy relations.

The announcement comes after three days of talks between the two sides in Sweden, and marks the most positive engagement between Pyongyang and the outside world in many months.