Ivor Caplin, who represented Hove as its MP from 1997 to 2005 and ultimately became a Labour government defence minister, was allegedly filmed on a Facebook Live video which saw him accused of arranging to meet an “underage boy”.
Caplin denied the allegations on the video multiple times before the police were called by the group.
The police were then seen to arrest Caplin, with officers saying he had been “detained on suspicion of engaging in sexual communication with a child”.
On Saturday, officers further confirmed “that a local 66-year-old man was arrested on Saturday January 11 and currently remains in custody”.
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The Daily Mail reported that locals in Hove had seen police officers search Caplin’s flat and allegedly seize items as evidence.
Reform UK leader Nigel Farage publicised the arrest on his Facebook account, sharing an image from the video of the vigilante sting. He wrote: “Former Labour defence minister Ivor Caplin has been arrested today after a sting by paedophile hunters.
“He allegedly attempted to meet a 15-year-old boy.”
In an update on Sunday, the force said the former MP has been released pending further investigations.
A spokesperson said: “A 66-year-old man who was arrested on suspicion of engaging in online sexual communications with a child on 11 January has been released on bail until 10 April while further enquiries are carried out.”