Leigh-Anne Pinnock was attacked by a crazed diner at a London restaurant recently.
The Little Mix singer was dining with pals at VQ restaurant, when they were approached by a man who started shouting abuse before slapping Leigh-Anne, 25, in the face and running off.
A source told The Sun: "He kept saying, 'if my girlfriend was here, you would both feel really intimidated.
"And then he said something like 'shut up' to Leigh-Anne's friend.
"Leigh-Anne turned around and said, 'don't say that to her' or 'don't be rude.'
"And he walked around the table and leant into her and gave her a clean slap on the face."
Leigh-Anne was left in tears by the incident and was spotted sobbing as she departed the restaurant.
The witness said: "He was really aggressive. He seemed like he had been drinking.
"She was laughing about it at first but then she completely broke down, crying. Her friend was comforting her.
"Leigh-Anne kept saying she wanted to go home.
She walked off hysterically crying.
"Her friend had her arm round her. She looked a mess and she was crying her eyes out."
A police spokesperson told the newspaper: "Police were called on Monday, 28 November at around 04:50 hours by a woman who stated that a man had threatened to assault her and had assaulted another woman she was with.
"The suspect made off prior to police arrival. Officers conducted a search of the area and did not locate the suspect."
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