Rescue teams have begun drilling into the walls of Tham Luang Cave in Chiang Rai province in a bid to speed up drainage of floodwater that is proving the biggest obstacle to rescue efforts.
The floodwater level is rising because of continued heavy downpours.
Thirteen members of a local football club – 12 boys and their coach – are still missing after entering the cave last Saturday. They are believed to have been stranded deep inside the 10-kilometre-long cave complex after flash floods sealed their exit.
