Lindsay Lohan banned from club
The former couple are said to have clashed at trendy nightspot Trousdale in Los Angeles on Friday, reported New York Post.
Witnesses claim Samantha was sitting with friends when Lindsay stormed up and threw her drink at the DJ's head, sending shards of glass flying in the air.
The onlookers claim Samantha, 32, was unhurt, but left badly shaken.
"Samantha was DJ-ing and went to sit with her friends when Lindsay stormed over and threw a glass at her head. Glass flew everywhere, and Samantha looked really shaken up. The club owner asked Lindsay to leave and was overheard saying she'll never come back," an onlooker told the newspaper.
Samantha, who continued to party with her pals, later wrote on Twitter, "Just got a glass thrown at my head... Hmmm - wonder who did it."
Last week, Lindsay, 23, had claimed Samantha "spat in her face" at a Coachella music festival party, but the DJ denied it.
Although the couple officially ended their stormy relationship last year, they still have a lot of contact with each other.
It has been an eventful few weeks for Lindsay. Police turned up with Lindsay's dad Michael at her Hollywood flat last week after concerns about her 16-year-old sister Ali's welfare.
She was also accused of stealing a 'friend's' Rolex watch, which she has since denied.