Louis Tomlinson has installed a panic room in his home.The One Direction star has spent £15,000 to build a safe area in his £2.5 million mansion in Hertfordshire, East England, to keep him and his guests safe after some jealous fans sent death threats to his girlfriend Eleanor Calder, 20.A source told The Sun newspaper: "Louis loves the fans and isn't overwhelmed with paranoia. He's just a realist about the dangers of being in the spotlight."One Direction followers are notorious for tracking the lads down, so that's made him a bit cautious. This is just something that makes him feel safe."Louis' girlfriend was previously targeted by trolls on Twitter, who sent the brunette beauty photographs of the singer's ex-girlfriend Hannah Walker before he lashed out at the comments made.He wrote on Twitter at the time: "I'm reading some horrible tweets - very p***** off! (sic)"Louis, 21, isn't the only member of the group to have high security in their home, with his bandmate Zayn Malik, 20, also having a panic room in his £2 million north London pad.However, fellow member Niall Horan has insisted he is "carefree" about people trying to intimidate the group - also formed of Harry Styles and Liam Payne - over the internet and doesn't let them bother him.He said: "It's only brave girls behind a computer, thinking they can say what they want. Other celebrities get freaked out about death threats. I'm carefree about them."