THE drama surrounding Monday morning's Kings Cross shooting took a chilling twist when NRL stars Willie Mason and Mark Riddell received a death threat that was being investigated by police. The threat comes just a day after Parramatta's international winger Jarryd Hayne had a shot fired at him by a drive-by gunman in a terrifying 4am attack at Kings Cross. A police spokesman revealed officers were treating the death threat seriously and had increased security around the Sydney homes of Mason and Riddell. A man telephoned The Daily Telegraph offices to say: "Tell Riddell and Mason they're next." Security at The Daily Telegraph telephoned police, who contacted the two players and told them to remain inside their homes. "I got a call from a detective-sergeant who told me not to go out," Riddell said. "All this has gone to a new level. I don't know what to say, it's a big shock. "(After the Hayne incident) we were warned there might be more. Of course I'm concerned. I just hope the police sort it out." Riddell spoke with Mason about the threat. "I'm not going anywhere tonight but you've got to try to lead a normal life," Riddell said. "You can't stay locked up all your life but they told us not to take any chances and stay indoors." Mason confirmed Surry Hills police contacted him about the threat. "I can't say anything -- the police have asked me not to comment at all," Mason said. Police confirmed that the pair had been the subject of a threat with detectives now trying to track down the anonymous caller. "Until police are satisfied that the call was a hoax, it was suggested to the men that they keep a low profile and certainly keep away from Kings Cross for the time being," a spokesman said. NRL chief executive David Gallop was concerned about the news. "It's a serious issue and one for the police to investigate," Gallop said. Meanwhile, Riddell las played down an alleged argument with Eels skipper Nathan Cayless at the Iguana Bar on Sunday night. There was speculation the two had a heated exchange with Mason breaking up the pair. There is no suggestion the incident was linked to the threat. "There was never an argument," Riddell said. "We're sweet. There was a bit of talk. Boys will be boys."