Fifteen fathers' rights protesters have been arrested after entering the Celebrity Big Brother compound and throwing fireworks early on Friday.
John McCririck and the other contestants slept through the stunt.
Hertfordshire police said 13 men and two women from the Fathers 4 Justice group were held on suspicion of conspiring to cause criminal damage.
They broke into the compound at the Elstree Film Studios at about 3am.
Studio security guards contacted the police, who used a helicopter to round them up at the Channel 4 show's site.
At least one of the group was dressed as Superman - a popular outfit for the protesters.
The police, who had been tipped off about a possible stunt, sent 12 officers and a police helicopter with heat-seeking equipment to the compound.
The helicopter was "a lot quicker than trying to round them up in the dark", Insp Paul Lazell said.
Fathers For Justice said it wanted "to raise awareness of the risks posed to young unmarried men who watch Big Brother and might become fathers but are not aware they have little or no rights in law to protect them".
The group's founder Matt O'Connor said a second raid on the house was planned for later on Friday, using "a form of air transport".
Mr O'Connor said the protesters had planned to climb onto the roof of the house and drop supplies in for the contestants.
He described security at the compound as "a damn sight tighter than at Buckingham Palace".
Two members of the campaign group managed to breach palace security on September 13 when they staged a protest dressed as Batman and Robin.
It appeared from live coverage of the Big Brother house that contestants continued to sleep as the protest progressed.
The first eviction will take place on Friday night with racing pundit John McCririck and the mother of Sylvester Stallone, Jacqueline, the first stars to face the public vote.