On-off girlfriend Samantha Ronson has allegedly beaten up Hollywood actress Lindsay Lohan.

The actress, who has a turbulent relationship with Samantha, reportedly told a friend how the romance had, at times, been very violent, with Lindsay having the scars to prove it, reported femalefirst.co.uk.

'One time I saw Lindsay and she had a large welt on her head. She told me that Sam beat the s**t out of her,' said a friend. 'She also said that Sam even punched and choked her one time.'

Although they have officially broken up, the two women still have regular contact with each other, which makes things hard on Lindsay.

This is not the first time Lindsay has made accusations about Samantha.

She once took to her Twitter page to berate Samantha, accusing her of cavorting with two other women.