A Twitter argument has broken out between One Direction's Louis Tomlinson, his former band mate Zayn Malik and producer Naughty Boy.
DJ and music producer Naughty Boy posted a picture of himself and Zayn on Twitter, writing "caption this".
A Tweet following that by Tomlinson seems to have sparked a spat on the Social Media site.
Tomlinson wrote: "Remember when you were 12 and you used to think those Mac filters for your pictures were cool haha ! Some people still do HA!"
Malik then took to Twitter, replying to Tomlinson writing: "Remember when you had a life and stopped making bitchy comments about mine?"
A war of words between Tomlinson and Naughty Boy has followed.
Some of Naughty Boy's Tweets, which he has tagged Tomlinson in, read: "And some people can't even sing.. but who's complaining when there's auto tune eh" and also "Yeah how does it feel mate? You've been doing that for the last five years... I've got Emeli Sande and Sam Smith on my CV."
Tomlinson's own replies include: "Jesus forgot you were such an in demand producer .... How does it feel to be riding on the back of someone else's career?" and also "Good for you, well done !! I think we've done alright in terms of sales and I've happened to write on most. Keep trying!"
Malik, who quit the band in a shock announcement in March, made his first public appearance at this year's Asian Awards. He also debuted a new look, a shaved head at the ceremony.
The former One Direction star took his mother as his date for the evening, leaving fiancee Perrie Edwards at home.
The 22-year-old was presented with the award for Outstanding Contribution to Music and thanked his former One Direction band mates.
He said: "I'd also like to take this moment to thank four of the best guys that I ever met whilst being in the band and doing all the amazing things that I did.
"Some of the things that we did will stay with me for the rest of my life."
DJ Naughty Boy - real name Shahid Khan - was also at the event.
Shortly after Malik quit One Direction, Naughty Boy posted a demo of song I Won't Mind, featuring Malik's vocals, online only to delete it 12 hours later.
Naughty Boy said: "I wouldn't call it working (with Malik). We're good friends, and I think in this business it's hard to make good friends, so that's what I'm here for. That's why I'm there for him right now."