Dina Lohan tells UsMagazine.com that her ex Michael -- who barged into Lindsay's L.A. apartment to stage an intervention Thursday -- is "dangerous."
"He has absolutely no rights to do this!" she adds. "He's a three-time felon."
Lindsay, 23, went on a Twitter rant to accuse her "ex-dad" of showing up to her apartment with "fake police" to check on her 16-year-old sister, Ali.
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"my lawyer isn't answering I NEED A RESTRAINING ORDER! MY SISTER AND FRIEND TOO!!!!! HE'S NUTS!!!" Lohan posted. "my BUILDING didn't STOP him, isn't it supposed to be safe? THAT'S WHY I MOVED HERE! it coulda been FAKE cops! dressed up... let's not forget, that my father KIDNAPPED me from a COURT ROOM when i was 4 years old and is CRAZY."
Michael tells Hollyscoop.com that he was worried about Ali after hearing she drove home "at 115 miles an hour" from the Coachella music festival this weekend with Lindsay.
"I went to the police department concerned about Ali's welfare," Michael says. "I wanted to check on Ali. I want to make sure she's OK. She's 16 and she doesn't belong there! She's a minor. I just want to make sure she's ok," says Michael.
"Ali is being exposed to nightlife and the people Lindsay is surrounding herself with," Michael continues.
Michael says he's meeting with Lindsay's attorney's today to consider getting a conservatorship, similar to Britney Spears and Jamie Spears.
"She needs help and I won't stop until she get it," he said.
A Los Angeles County Sheriff spokesperson tells Us, "We were there. We found no evidence of abuse."
Lindsay has blamed her past troubles with cocaine on her father, a former drug addict.
"I was only aware of cocaine because of my dad," she told Britain's The Sun last February. "I was terrified of it. But I tried it because I was stubborn, stupid, and wanted to see what it was like."
Police found Lindsay to be in possession of cocaine in two separate DUI incidents in 2007. She went to rehab three times.