All 22 North Koreans who were voluntarily returned to their country early this month are known to have been executed.

A source said rumors have spread that North Korean police executed all of them without sending a single one to a labor camp.

The 22 North Koreans were rescued by the South Korean Navy while drifting on a rubber boat in South Korean waters February 8. But a Seoul official said they all said they wanted to return to the communist country.

If their executions are confirmed, Pyongyang will likely come under harsher criticism for human rights violations.

The National Intelligence Service in Seoul said the 22 North Koreans comprised eight men and 14 women, with 13 of them relatives.