Police arrested two fathers’ rights campaigners after they sprayed fart gas through the letterbox of a trade union office in Wandsworth.

Fathers 4 Justice claim two campaigners caused the stink at the NAPO office in Chivalry Road near Clapham Junction at 1pm on Friday.

The campaigners, including one from Epsom, targeted the union, that represents family court and probation workers, because they “wanted to get the message across that the bias family laws system and those that support it stinks”, according to a spokesperson for the protest group.

The office was not evacuated but police said they were called to the scene after a pungent whiff was left behind by a foam like substance sprayed from a can.

No one was injured but the two men were arrested.

Police could not confirm at this time if they were released or charged following questioning.

A Fathers 4 Justice spokesman said the action was the start of a series of stunts planned by the campaign group, that fights for fathers rights in the family court system.

The campaign group hit the headlines last month when its protestor John Paul Stanesby, 43, was jailed for two months after scaling deputy Labour leader Harriet Harman’s Herne Hill home dressed as a super hero.

Dressed as superhero "Captain Conception" he unfurled a banner from a bedroom window reading "A Father is for life, not just conception" during the protest in June.

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