Undercover police agents in the UK infiltrated environmental groups, had sex with their members, struck up long-term relationships with women in these groups, fathered children with these women, and then abandoned the children.

Two undercover police officers secretly fathered children with political campaigners they had been sent to spy on and later disappeared completely from the lives of their offspring, the Guardian can reveal.

In both cases, the children have grown up not knowing that their biological fathers – whom they have not seen in decades – were police officers who had adopted fake identities to infiltrate activist groups. Both men have concealed their true identities from the children's mothers for many years.

Good thing the police were there, though. Who knows what kind of unethical behaviour an environmentalist might be getting up to.

Undercover police had children with activists