Asia and forced to sign contracts, according to a BBC investigation.
Six minors are still with top Laos side Champasak United, after it imported 23 under-age players from West Africa to an unregistered football academy in February.
FIFA regulations prohibit the movement of players to a foreign club or academy until they are 18.
The club, based in the southern city Pakse, has denied any wrongdoing.
“FIFA is in contact with several member associations in order to gather all information to assess the matter and safeguard the interests of the minors,” a FIFA spokesperson told the BBC.
Global players’ union FIFPro, which helped release 17 of the 23 players three months ago, said in a statement it “suspects this case is not one of its kind, but probably the tip of the iceberg”.
It has been claimed that Champasak United, a newly-formed club which plays in Laos’s top league, intends to profit by selling the players in future.
In a clear breach of the world football governing body’s rules, the club has fielded overseas players as young as 14 and 15 in league games this season.
One 14-year-old player, Liberia’s Kesselly Kamara said he was forced into signing a six-year deal before playing for the senior team.
His contract promised him a salary and accommodation, but Kamara said he was never paid and had to sleep on the floor of the club’s stadium –– as did the rest of the travelling party.
“It was very bad because you can’t have 30 people sleeping in one room,” Kamara, who is now playing for a club back home in Liberia’s top league, told the BBC.
Kesselly Kamara, 14, says he was never paid and had to sleep on the floor of the club’s stadium.
All those who travelled to join the “IDSEA Champasak Asia African Football Academy” did so after being invited by former Liberia international Alex Karmo, who captained the club at the time.
Young players gratefully accepted the invitation, since Liberia lacks a football academy of its own, despite being the only African country to have produced a FIFA World Footballer of the Year –– George Weah in 1995.
“It’s an ‘academy’ that has no coach nor doctor. Karmo was the coach, the business manager, everything. It was completely absurd.”
Following initial pressure from both FIFPro and FIFA, Champasak released 17 teenagers from the original party, with Kamara among them, by early April.
But six minors chose to remain.
FIFPro says that all have since signed contracts presented to them by Karmo, who describes himself as a “manager for players from Africa in Champasak”, and club president Phonesavanh Khieulavong.
These appear to allow Champasak to pay the boys nothing at all, while also demanding that unrealistic conditions be met should the teenagers want to leave.
Karmo says the players are fed three times a day and paid every month.
“We don’t give the [minors] professional contracts, just a contract that gives them bonuses,” Khieulavong told the BBC.
Neither Khieulavong nor Karmo denied the presence of minors at the academies, although Karmo claimed there was just one –– a 16-year-old from Guinea.
The BBC understands there are five more minors from Liberia at the club.
Along with eight senior players (six Liberians, a Ghanaian and Sierra Leonean), all are living in conditions described as “deplorable and disturbing” by Bedell.
For five months, they have been sleeping on meagre mattresses in a vast room that lacks any glass on its windows and a lock on the door.
Footballers’ sleeping quarters.
The minors’ freedom of movement is restricted by the fact that they became illegal immigrants in March after their visas ran out.
“This is a very serious situation,” Stephane Burchkalter, a FIFPro official, told the BBC.
“It is shocking to FIFPro that a club from Laos, which –– with all due respect –– is a very small football country, can lure minor players from Liberia without FIFA noticing.”
It is estimated that 15,000 teenage footballers are moved out of West Africa every year –– many of them illegally.