Undercover policing laws are ambiguous to the point where ordinary people are at risk of having their private lives infiltrated, an influential group of MPs has warned.
Unacceptable sexual relationships and the "ghoulish" use of dead children's identities by undercover cops has offered compelling evidence for an urgent review of legislation, the House of Commons Home Affairs Committee said.
A lengthy Metropolitan Police investigation into misconduct by undercover officers should be completed with "all possible haste", the committee added, while police chiefs should be stripped of their role in setting standards for covert policing.
A raft of allegations have been made since former PC Mark Kennedy was unmasked in 2011 as an undercover officer who spied on environmental protesters as long-haired dropout Mark "Flash" Stone and had at least one sexual relationship with one of the activists.
Committee chairman Keith Vaz MP said: "We are not satisfied that the current legislative framework provides adequate protection against police infiltration into ordinary peoples' lives - a far more intrusive form of surveillance than any listening device or hidden camera."
Five women and one man are suing the Met Police over alleged intimate relationships with undercover police, including cases where children have been fathered.
It has also been reported that one officer planted a bomb on behalf of an animal rights group and that another was prosecuted under his assumed persona.
The committee said the terrible impact on the women's lives was "beyond doubt" with "risk to their psychological well-being", adding "there are some lines police officers must not cross".
In its interim report, the committee called for an urgent review of the Regulation of Investigatory Powers Act (Ripa) as there was an "alarming level of inconsistency" among ministers and senior police officers over the limits of the law.
It said: "We believe that the current legal framework is ambiguous to such an extent that it fails adequately to safeguard the fundamental rights of the individuals affected. We believe that there is a compelling case for a fundamental review of the legislative framework governing undercover policing."