Mae Sai, Jun 27 (AFP) Rescuers battled heavy rains today as they struggled to drain a flooded cave in Thailand where 12 children and their football coach have been trapped for days, as desperate relatives clung to hope the boys will be rescued soon.

The young football team, aged between 11 an 16, have been stuck in the Tham Luang cave in northern Thailand since Saturday night after monsoon rains blocked the main entrance.

Hundreds of rescuers worked overnight to install high-pressure water pumps to reduce flooding in the cave, but it was a losing battle as rains continued to pound the area in northern Chiang Rai province near the Laos and Myanmar borders.

"Rising water levels is major obstacle in the rescue operation, and it rained hard last night," Khanchit Chomphudaeng, the provincial secretary in charge of the rescue operation, told AFP.

He said 1,000 people had been mobilised for the search, including air and ground teams and divers. The Army also dispatched special operation troops to aid the rescue.

Thai Navy SEAL said on their Facebook page that water levels rose 15 centimetres (six inches) overnight and that a third chamber of the complex cave network, believed to be several kilometres long, was now flooded.

Soldiers carried large hoses into the cave Wednesday to continue draining rising flood waters, according to an AFP reporter at the scene.

Distraught relatives have been camped out for days praying for the team's safe return.

"I hope that today with the help from all teams he will be saved. I'm certain in my heart," Pean Kamlue, the mother of a 16-year-old boy in the cave, told AFP.

The harrowing rescue operations have captivated the country and prompted emotional outpourings on social media and from the country's top leaders.

Officials said late last night they spotted a second opening into to cave and would try to lower divers and supplies into the hole as helicopters were dispatched to survey the area.

Soldiers also scoured the scene on foot overnight searching for more entry points.

The young football team, called the "Boars", and their 25-year-old coach are familiar to the area and know the cave well, officials said.

They went into the cave after football practice on Saturday and a mother of one of the young players alerted authorities when her son did not come home.

Bicycles, shoes and backpacks belonging to the young footballers were found near the cave's entrance, and divers said they discovered footprints and handprints inside one of the chambers on Monday.

A sign at the cave's entrance warns visitors not to enter the cave during the rainy season from July to November.

Rains were forecast all day today.(AFP)

(This is an unedited and auto-generated story from Syndicated News feed, LatestLY Staff may not have modified or edited the content body)