London, April 10 : Former Spice Girl Geri Halliwell is said to be terrified after being targeted by a crazed stalker.

The singer has tightened security at her north London house to protect herself and two-year-old daughter Bluebell from the loner, who hangs around outside at all hours.

Halliwell also had to change her phone number after constant nuisance calls.

"Geri has become increasingly concerned over recent months. This individual has been loitering around her home almost continually and it's really upsetting and scaring her," the Sun quoted a friend, as saying.

"Her burglar alarm has gone off a number of times when she's been out and she's worried about her and Bluebell's safety.

"The phone was ringing at all hours of the day and night so she had to get a new number," the friend added.

This isn't the first time Halliwell, a UN Goodwill Ambassador, has been threatened.

Last year in June, she was abused by a raving woman at a glitzy bash in London.

A source said: "Geri is acutely aware that life in the public eye brings with it certain unwelcome elements.

"She has been in the spotlight for around 15 years so knows perfectly well that some members of the public can get a little too devoted.

"When she was in the Spice Girls they were trailed night and day by obsessional fans.

"But this latest episode is a little more serious than that and she's not prepared to take any risks with her daughter's wellbeing," the source added. (ANI)