Arthur Collins is wanted for questioning after 20 people were injured when corrosive liquid was sprayed at Mangle in Dalston, east London.
The 25-year-old, from Hertfordshire, has been in a relationship with Ferne, best known for her appearances on The Only Way Is Essex and I’m A Celebrity…Get Me Out of Here!
Two clubbers, aged 24 and 29, were seriously hurt in the attack, which followed an argument, early on Monday morning and have been moved to a specialist burns hospital in Essex.
Police said Collins should not be approached, urging members of the public to instead ring 999.
They added an address in Hertfordshire was raided on Monday night by officers carrying out an arrest warrant in connection with the attack.
A spokeswoman for Ferne said: “Ferne is aware that the police wish to speak to Arthur Collins and the nature of the accusations against him. Obviously these are highly shocking and Ferne has co-operated with the police in their inquiries.
“She was not with Arthur on Sunday night; was not at Mangle; and has no direct knowledge of the events that unfolded. As much as anybody she wants to know the truth and urges Arthur to co-operate fully with the police and attend a police station immediately.”
Ten people were taken to hospital for burns, while two others with similar injuries sought treatment, emergency services said.
Detective inspector Lee McCullough said: “We now have 20 people suffering from the effects of an acidic substance being sprayed in a confined space in a busy nightclub.
“All have burn related injuries. The noxious substance used has not yet been confirmed but samples retrieved from the scene have been sent for analysis.
“If you were there and saw anyone involved inside or leaving the nightclub, please get in touch.”
One eye-witness said the faces of two black men were turned white by the acid and they were unable to see.
The police search for Collins comes just one day after Ferne revealed the couple had plans to wed.
In an interview with OK! magazine, the 26-year-old said: “We’ve spoken about our wedding.
“We want to get married on a beach. I want it to be a party and a celebration.”
She said the pair had met on Instagram last August.