London (CNN) A hotline set up for people who were sexually abused while playing soccer in Britain as children has received more than 50 calls in its first few hours, the National Society for the Prevention of Cruelty to Children says.

The service was launched Thursday morning, with the support of England's Football Association (FA), after former English footballers Andy Woodward, Steve Walters and Paul Stewart spoke to British media about being sexually abused as children. Another player, David White, has also come forward.

Chief executive of the National Society for the Prevention of Cruelty to Children (NSPCC) Peter Wanless said: "There must be no hiding place for sexual abuse in our national game and there may be many others who suffered through such horrors as young players but have never come forward."

Coach jailed for abuse

Former Sheffield United player Woodward was the first to tell his story publicly, explaining how he was abused by coach Barry Bennell while playing for Crewe Alexandra football club, in northern England in the 1980s and 1990s.

Bennell was jailed in 1998 for nine years after admitting to sexually abusing children, including Woodward.

Stewart, who played for Liverpool and Tottenham Hotspur, said another coach had repeatedly sexually assaulted him and threatened to kill his family if he spoke out.

Just sat in bed reflecting on the past week. Words can never say how thankful I am for all your support. This momentum WILL save people. — Andy Woodward (@AndyWoodward2) November 24, 2016

Woodward's and Walters' Twitter accounts have been flooded with support in recent days. "This momentum WILL save people," Woodward wrote. Walters said he was "totally taken back" by the support he had received since opening up about the abuse he suffered.

Can I please thank everyone for the incredible support so far I'm totally taken back with it, know now I've made the RIGHT decision ❤️❤️ — Steve Walters (@steven_walters4) November 23, 2016

'Safe haven' needed

In a statement appealing for others affected by child abuse in the sport to come forward, the NSPCC said boys were less likely to speak up about sexual abuse.

"Football locker rooms and clubs are traditionally very masculine and male environments. This means it can be difficult for players to talk about issues such as sexuality or abuse.

"But it's crucial they speak out. Along with the FA, we're urging players and others involved in football, from those just starting out to Premier League, to [use] our helpline," the charity said.

Detective Inspector Sarah Hall of Cheshire Police's public protection unit told the Press Association Wednesday that "we have now been made aware of a number of people who have come forward wishing to speak to the police" with similar claims.

She said no arrests had been made so far.

Gordon Taylor, chief executive of the Professional Footballers' Association, said it was a "timely warning for everybody in football about our duty of care to these youngsters" and that he wanted the union to be a "safe haven," the Press Association reported.