1. When Salman Khan and Shah Rukh Khan had a physical fight during Katrina Kaif's birthday.
This happened back in 2008. Salman and Shah Rukh got into a tussle apparently over some issue that involved Aishwarya Rai. The fight got really ugly and physical. Speaking on the matter, Shah Rukh later noted:
I was very ashamed over the Salman issue. I hope it never happens to me again. I didn't know how to explain it, and finally told them, "There are some people who just don't get along".
2. When Harbhajan Singh slapped Sreesanth after an IPL match.
Also something that happened in 2008. The two, playing for Mumbai Indians and Kings XI Punjab respectively, had a bit of a tiff and Harbhajan slapped Sreesanth. The images of a crying Sreesanth started making headlines and are discussed to date.
3. When Salman Khan allegedly threatened Vivek Oberoi and the latter held a press conference regarding the same.
The two had a fight over Aishwarya Rai and Salman apparently called Vivek while he was drunk, and threatened to harm him. Vivek then called a press conference and showed that Salman had called him 41 times.
4. When Kangana Ranaut called Hrithik Roshan a "silly ex" and that led to not just a war of words, but also legal notices.
Hrithik Roshan kept denying that he had anything to do with Kangana. While Kangana said that he dated and misled her. Anyway, things got out of hand when Hrithik filed a legal complaint against Kangana and she filed a counter-complain. This went on for months and emails were leaked, completely opposite narratives were made and a lot was said from both sides.
5. When Shah Rukh Khan allegedly slapped Shirish Kunder for his remarks on Ra.One.
Ra.One was Shah Rukh's passion project and did not have the impact people were expecting it to. So, during a party, Shirish Kunder decided to make comments about the same and allegedly called the movie a "150-crore firework frizzle". Shah Rukh did not like this at all, and reportedly got physical with him.