The dispute began when the ex-Only Way Is Essex star posted a link to a photograph of the two together last night (May 3).
In the accompanying tweet, she wrote: "Drink down my dress. Marcus Collins who said he felt like he was workin when I asked for a pic #Bigtime (sic)."
The X Factor UK singer then tweeted in response: "Does anyone know who this girl is? Whoever she is she is very Very rude and needs to calm down #whythelongface."
Matters then escalated, with Fowler writing: "Ooh Marcus asked why I called him bigtime (because he is) I said coz u were rude so he called me fake n spat in my hair #ouch #big time."
Collins responded: "Called 'a f****** queer c***' by @MariaFowler, not standing for homophobic abuse by anyone it's unnessasry and I never spat in anyone's hair (sic)."
He also wrote: "Some people should be ashamed of themselves #homophobia will NOT BE TOLERATED @MariaFowler #Ignorant."
Fowler shot back: "Throwing the gay line for record am with 4 gay guys here certainly not homophobic. No excuse #everyonesaw rude n ur 'people."
At one point, Collins also tweeted: "Swear I heard her say something racist? Didn't want to Bring it up." However, when Fowler wrote "Call me rascist (sic) I will sue you for defamation", the tweet was removed.