Soap bubbles found in a stream in Wang Kelian, Perlis led to the shocking discovery of illegal migrants, the Royal Commission of Inquiry (RCI) heard on Wednesday.

Kpl Mat Ten said he took cover behind a rock and discovered an unattended shop, observation posts and wooden bridges between trees.

The incident is being probed by a seven-member panel led by former chief justice Tun Arifin Zakaria and assisted by former Inspector-General of Police Tan Sri Norian Mai.