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In this Monday, July 2, 2018, file photo, Thai police stand in front of the entrance to a cave complex where 12 boys and their soccer coach went missing in Mae Sai, Thailand.Sakchai Lalit/The Associated Press

A Thai rescuer has died after falling unconscious during part of an operation to rescue 12 boys and their soccer coach trapped inside a cave complex in northern Thailand.

Samarn Poonan, a former member of Thailand’s elite navy SEAL unit who was part of the rescue team in Chiang Rai, died on Thursday night after entering the cave to lay oxygen tanks along a potential exit route, the SEAL commander said.

Rescuers are trying to find alternative ways to conduct the rescue as teams brace for heavy rain which could further delay the operation.

“We are trying to find alternative techniques to reach the 13,” Chiang Rai Governor Narongsak Osottanakorn told reporters late on Thursday.

“We have considered many alternatives to find the most feasible ones,” he added.

Rescue alternatives include teaching the boys to dive and then swim out, a highly risky venture, remaining in the cave for months until the wet season ends and flood waters recede, or drilling a shaft into the cave from the forest above.

THAM LUANG

CAVE SYSTEM

Chiang Rai

Cave

location

THAILAND

THAILAND

Bangkok

The team is 965 m

underground.

The CN Tower is 553 m

(to scale)

0

300

KM

The team was found 4 km from

the entrance. it takes five to six

hours to travel the distance due to

all the water and obstructions.

More than half of the route is flooded.

1,275.9

metres

“Pattaya

Beach”

400 m from

team

There are areas where

full climbing equipment

is needed

Entrance

to cave

Some of the flooded

diving areas are too

narrow to wear scuba

tanks

Some diving areas are

so long, with such poor

visibility that rescue divers

installed guide ropes and rows

of air tanks every 25 m

TRISH McALASTER / THE GLOBE AND MAIL

SOURCES: CNN, BBC, DAILYMAIL.CO.UK

THAM LUANG

CAVE SYSTEM

Chiang Rai

Cave

location

THAILAND

THAILAND

Bangkok

The team is 965 m

underground.

The CN Tower is 553 m

(to scale)

0

300

KM

The team was found 4 km from

the entrance. it takes five to six

hours to travel the distance due to

all the water and obstructions.

More than half of the route is flooded.

1,275.9

metres

“Pattaya

Beach”

400 m from

team

There are areas where

full climbing equipment

is needed

Entrance

to cave

Some of the flooded

diving areas are too narrow

to wear scuba tanks

Some diving areas are so long,

with such poor visibility that

rescue divers installed guide ropes

and rows of air tanks every 25 m

TRISH McALASTER / THE GLOBE AND MAIL

SOURCES: CNN, BBC, DAILYMAIL.CO.UK

THAM LUANG CAVE SYSTEM

Chiang Rai

Cave location

The team is 965 m

underground.

The CN Tower is 553 m

(to scale)

1,275.9

metres

THAILAND

Bangkok

The team was found 4 km from the entrance.

it takes five to six hours to travel the distance

due to all the water and obstructions.

More than half of the route is flooded.

0

300

KM

There are areas where

full climbing equipment

is needed

“Pattaya Beach”

400 m from team

Entrance

to cave

Some of the flooded

diving areas are too narrow

to wear scuba tanks

Some diving areas are so long, with such poor

visibility that rescue divers installed guide ropes

and rows of air tanks every 25 m

TRISH McALASTER / THE GLOBE AND MAIL; SOURCES: CNN, BBC, DAILYMAIL.CO.UK

The boys, aged between 11 and 16, and their assistant coach were found inside the Tham Luang cave in northern Chiang Rai province on Monday, after nine days underground, hungry but in good spirits. They went missing after they set out to explore the cave on June 23.

Rescuers are now deciding how to remove the group but have been slowed down by logistical issues including high water levels inside the cave and narrow, flooded passages which would require the boys to dive alone.

The Thai navy is now teaching the boys the basics of diving, with a view to guiding them out through flood waters.

But getting them out won’t be easy. The boys will have to be taught how to use scuba diving gear and how to navigate a cave that has frustrated even the most expert divers.

“Regarding the plan for the 13 to swim or dive, there is only one critical point which it is risky: It is where every boy has to dive alone. The point is very narrow … It is very deep water. The distance is pretty long,” said Narongsak.

Some of the boys cannot swim.

But rescuers are also considering other options including keeping the 13 inside the Tham Luang cave until the flood waters recede, at the end of the rainy season in about four months.

Others say the boys could be out in days if the weather is on their side and enough water can be pumped out of the cave to enable the boys to get out the same way they got in, on foot, perhaps with some swimming.

Another possibility would be to find an alternative way into their chamber, such as drilling a shaft into the cave from the forested mountain above.

Narongsak said rescuers were preparing a five km (three miles) “oxygen pipeline” as part of preparations for the group’s extraction but added that the boys would not be coming out soon.

“You see we are increasing the number of people going inside the cave. So we have to fill it up with oxygen,” he said.

Heavy monsoon rains are forecast for next week in most of the north, according to Thailand’s meteorological department.

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