• Three players – including manager’s son – filmed in orgy • ‘We will take action, if necessary, once the full facts have been established’

Three Leicester City players have apologised after they were filmed in an orgy with a Thai woman who was racially abused. The club has said it is “deeply concerned” and has launched an investigation after calls for the trio to be sacked.

The footage, obtained by the Sunday Mirror, allegedly shows the 22-year-old defender James Pearson, the son of the club’s manager, Nigel, the striker Tom Hopper, 21, and the goalkeeper Adam Smith, 22, naked in a Thai hotel room as women are filmed engaged in sex acts. In a clip of the video posted on the newspaper’s website, one of the men appears to be heard calling one of the women a “slit eye” in a racist slur.

Later one calls one of the women “minging – an absolute one out of 10” as his friends laugh. Other offensive comments are made to the women as the players appear to laugh and egg each other on. It is alleged the trio shared the explicit video with friends back in the UK.

In a statement the club said the players “would like to convey their sincere apologies for their behaviour – to the women involved in the incident, to the club and its owners, to the club’s fans and to their families”.

Earlier Leicester City had released a statement saying: “We take the conduct of our players at every level extremely seriously and will take appropriate action, if necessary, once the full facts of the situation have been established. Pending the outcome of an internal investigation the club will make no further comment.”

The club, currently touring Thailand celebrating their successful battle against relegation from the Premier League, is owned by the Thai billionaires Vichai and Aiyawatt Srivaddhanaprabha and has been in “strategic, international partnership” with the Tourism Authority of Thailand for three years. The tourism authority’s Amazing Thailand branding is on the back of team shirts.

Commenting on the partnership last year, Susan Whelan, Leicester City’s chief executive, said: “We’re absolutely thrilled to continue to work with the Tourism Authority of Thailand during the 2014-15 season. Their support in the last two years has been vital in helping us promote Leicester City to a Thai audience and in reaching our goals closer to home.”

Thawatchai Arunyik, governor of Tourism Authority of Thailand, said: “We are very proud to be working with Leicester City and its supporters, who have embraced the club’s increasingly strong association with Thailand and given the nation a Premier League football club its people can take to their hearts.”

On Sunday fans told of their disgust on the fans forum FoxesTalk, where one posted: “Get rid of them, never getting near our squad anyway.”

Another wrote: “Disgusting and inexcusable behaviour, exactly the sort of stuff that gives British tourists a bad name when we go abroad. It’s especially disappointing given the efforts the owners are going to to ensure we’re a popular club in Thailand.”

A Kick It Out spokesman said: “We are aware of the allegations and have contacted Leicester City Football Club. We will await their response before commenting further.”

Nigel Pearson has campaigned against racism and is a patron of the charity Show Racism the Red Card. A number of Thai people told of their outrage in comments posted on the Leicester City Facebook page.