R&B star Beyonce Knowles has reportedly beefed up her security for upcoming concert in Twickenham due to an obsessed fan.
The 31-year-old singer has ordered her staff to look out for a fan named Bassey Essien, who has been sending her threatening letters, reported Daily Mirror.
Beyonce had won an anti-harassment order in the High Court two years ago, prohibiting him from pestering her.
Essien has been sending threatening letters since 2009, court papers revealed.
"Staff have been briefed on the situation and pictures of him have been passed around. They've been told to keep their eyes open and be extra vigilant," a source said.
Beyonce's spokesman refused to comment.
