A group of North Korean escapees are seeking to determine whether inmates at a political prisoners’ camp in the North are dead or alive.

The group, which consists of escapees that were once detained at the “Yo-deok” prisoners’ camp, drew up a list of 187 inmates for delivery to the North Korean embassy in London on Wednesday.

The group tried to pass on the list, along with a letter to North Korean leader Kim Jong-il, but was denied by embassy officials. The group then resorted to slipping the materials under the door of the embassy building.

In their letter to the reclusive leader, the former inmates urged Pyongyang to improve its human rights situation and confirm whether the named inmates of the camp are dead or alive, adding that the international community has a keen interest in the North’s poor human rights conditions.