Lund filed a report Wednesday after Sambora said he would make her "disappear," a source told the magazine. She also allegedly has recordings of threatening phone calls from the rocker.
The musician and Lund first began a relationship 10 years ago and have been on and off ever since. According to the source, they last split two years ago, but a rep for Sambora claims the couple hasn't been together in six years. The source said the relationship between the couple, who founded the Nikki Rich clothing line together, has gone particularly sour this year, and that Sambora physically abused Lund in a meeting in January.
"After this, he retweeted something about Nikki being a nobody and a drug addict, and then started calling her cell and threatening her saying, 'I will make you disappear. I have millions of dollars and I can make people disappear - you are nothing,' " the source continued.
A rep for Sambora denied Lund's charges, calling them "contradictory, press-seeking, flash allegations." The rep said the pair's clothing line is failing and these claims are merely a way Lund can get money from Sambora.
"This is a cluster of fabricated lies in retaliation for Mr. Sambora's decision to cease further funding of the unprofitable partnership, plain and simple," said the rep.
Lt. Jennifer Seetoo confirmed that the Los Angeles County Sheriff's Department is investigating a criminal threat report filed this week, but didn't name the parties involved.