A rescue team, whose members now include a Navy SEAL unit, are continuing their concerted search for the missing 12 young footballers and their coach who have been trapped inside a cave in Tham Luang Khunnam Nang Non Forest Park in Mae Sai district since Saturday.
The flash flood that hit the area prevented the missing group from leaving the cave.
Latest reports indicate that the SEAL team, who arrived at the scene at about 2.45am on Monday morning, went into the cave and drilled into the wall of a cavern in which the youngsters were believed to be sheltering but to no avail.
However, rescue team members who entered the cave found footwear thought to belong to the young footballers of The Ban Phong Pha team, which is known in the area as "Moo Pa" (wild pig).
As the search operation continued yesterday for the 12 youths and their 25-year-old coach, their parents prayed for their safe return.
Deputy national police spokesman Pol Colonel Krissana Pattanacharoen summarised the search activities of Monday's search attempt, based on reports from Chiang Rai police.
00.10am: Ten search members of the Army and border patrol police enter the cave.
00.40am: A three-member team from the Mekhong Riverine Unit Headquarters joins the first team inside the cave to help locate the missing group.
1.20am: Authorities hold a meeting at the site to map the search efforts.
2am: The meeting agree that the Thai Navy's SEAL unit should join the search.
2.45am: A team of 18 SEALs arrives at the scene. They are briefed on the latest situation and decide to divide into four groups each with four members.
6am: They enter the cave and drill into the wall of a large cavern where the missing group is believed to be resting. After finding no one, the team continues searching.