Three American prisoners released by North Korea ahead of summit: Trump

Three Americans detained in North Korea for months are on their way back home, a "very exicited" President Donald Trump announced today, ahead of his historic summit with Kim Jong-un.

The Americans, Kim Dong Chul, Kim Hak-song and Kim Sang Duk, are travelling back to the US with Secretary of State Mike Pompeo, who called on North Korean leader Kim today during a previously unannounced visit to Pyongyang.

Trump said North Korea has released the three Americans and he would be there to receive them at the airport in the wee hours of Thursday.

"I am pleased to inform you that Secretary of State Mike Pompeo is in the air and on his way back from North Korea with the 3 wonderful gentlemen that everyone is looking so forward to meeting. They seem to be in good health," Trump announced in a tweet.

"Secretary Pompeo and his "guests" will be landing at Andrews Air Force Base at 2:00 A.M. in the morning. I will be there to greet them. Very exciting!" Trump said in another tweet.

The fate of the detainees has been a key factor in the build up to the Trump-Kim meeting.

While Kim Dong Chul has been in North Korean custody since before Trump was elected, the other two detainees were arrested last spring, after Trump's inauguration and as tensions between Washington and Pyongyang were beginning to ramp up, CNN reported.

Kim Sang Duk and Kim Hak-song, who were arrested in April and May of 2017, respectively, were both accused of carrying out "hostile acts" against the Kim regime.

Both worked at the Pyongyang University of Science and Technology, which bills itself as the only privately run university in the North Korean capital.

Trump had hinted at a potential development in their case last week in a tweet: "As everybody is aware, the past Administration has long been asking for three detainees to be released from a North Korean Labor camp, but to no avail. Stay tuned!"