The London police department has paid 425,000 pounds in compensation to a woman who discovered that the man with whom she bore a child was actually an undercover police agent whose job was to spy on her activities, officials said.

Scotland Yard, also known as the Met, apologised “unreservedly” for causing pain and suffering to the woman, identified by authorities only as Jacqui.

Police paid the compensation after a legal battle which began when Jacqui found out in 2012 that the father of her child and with whom she had maintained a relationship during the 1980s, had seduced her deliberately to monitor her political activities.

The compensation was part of a settlement offered to the woman if she would withdraw her lawsuit against the police in which she accused them of assault, negligence, fraud and misconduct of an agent.

Jacqui told the BBC that she had to receive psychiatric treatment after discovering the true identity of the agent, whom she knew as Bob Robinson, was actually named Bob Lambert and that he worked for the Special Demonstration Squad.

This unit performs long-term covert operations designed to infiltrate various groups, including organisations defending the rights of animals.

For Bob Lambert, the mission was to infiltrate the Animal Liberation Front. As part of an operation in the 1980s, he began an affair with Jacqui who was 22 years old at the time.

In 1985, Jacqui gave birth to a child from her relationship with the agent who disappeared when the child was two years old.

Jacqui criticised the police for not wanting to admit that what they did was totally unacceptable and said she was unaware of why the police wanted to know details of her activities.