Police chiefs have admitted for the first time that undercover officers gathered intelligence on the family of murdered teenager Stephen Lawrence who were campaigning for a better investigation into his killing.

Mick Creedon, the Derbyshire chief constable conducting an investigation into the activities of police spying on political groups over 40 years, told MPs on Tuesday that his inquiry had discovered information on the Lawrence family in the files of the undercover officers.

The undercover intelligence-gathering was brought to the attention of Sir Bernard Hogan-Howe, the Metropolitan police commissioner, earlier this year, Creedon added.

Hogan-Howe had been notified before a police whistleblower told the Guardian last month that he had participated in an operation to spy on the Lawrences and campaigners angry at the failure to bring his killers to justice.

Earlier in the day, Hogan-Howe addressed another aspect of the controversy surrounding the use of police spies by his force. In a report, the Met chief admitted that at least 43 undercover officers had stolen the identities of children who had died before they were 14.

Hogan-Howe offered a general apology, but he refused to tell any specific families that the identities of their children were used by the undercover officers.

The Met commissioner said he "should apologise for the shock and offence the use of this tactic has caused" among the public. But he argued the families of children whose identities had been stolen by police could not be informed as it could lead to the exposure of the undercover officers sent to infiltrate the political groups.

"It was never intended or foreseen that any of the identities used would become public, or that any family would suffer hurt as a result. At the time this method of creating identities was in use, officers felt this was the safest option," he added.

The widespread theft of the identities of dead children by undercover police has been dubbed the "Jackal run", after Frederick Forsyth's fictional depiction of the practice.

Creedon is examining the conduct of a covert Metropolitan police unit known as the Special Demonstration Squad (SDS), which infiltrated political campaigns between 1968 and 2008 – and in particular claims made by Peter Francis, the whistleblower who infiltrated anti-racist groups between 1993 and 1997.

It was Francis who revealed that undercover officers sought to gather evidence on the Lawrence family. He has said his superiors wanted him to find intelligence that could be used to undermine the family and those campaigning for a better investigation into the murder.

Creedon told the Commons home affairs committee that at some point this year his inquiry found documents recording "covert deployments which reported intelligence which relate" to the Lawrence family and that Hogan-Howe was made aware of this.

He added that the intelligence had been collected as the undercover officers were spying on what he said were "violent protest groups" campaigning for a proper police investigation into the teenager's murder.

Creedon argued spies were deployed to gather intelligence because there was a belief that such groups "may well hook on to any high-profile incident as a vehicle for their violent protests". He added: "The fact that an undercover deployment made a reference to the Stephen Lawrence family does not mean there was an undercover deployment against the Stephen Lawrence family."

Doreen and Neville Lawrence, the parents of the murdered teenager, have said they have no confidence in inquiries run by Creedon and by a barrister, both of which were asked last month by home secretary Theresa May to examine Francis's claims. Francis has not spoken to either inquiry as he shares the Lawrences' lack of confidence in them.

Creedon told MPs on Tuesday that in the three weeks since the claims were made, he had uncovered no evidence to show the police had attempted to use the intelligence gathered to smear the Lawrences.

In February, Francis was also the key whistleblower behind revelations in the Guardian that detailed the theft of the children's identities.

The report by Creedon, published by Hogan-Howe, showed the technique was used extensively as far back as 1976 and was authorised by senior police officers. Creedon reported that the tactic became "an established practice that new officers were taught" within the SDS.

"This was not done by the officers in any underhand or salacious manner – it was what they were told to do," he added.

One senior spy is quoted as saying an undercover officer would spend "hours and hours … leafing through death registers in search of a name he could call his own".

"The genuine identities of the deceased children were blended with the officer's own biographical details," Creedon said.

The Special Branch spies were issued with fake documents, such as passports and driving licences, to make their alter egos appear genuine in case suspicious activists started to investigate them.

The last time the tactic was used, according to Creedon, was 2003, by a spy working for a second covert unit – the National Public Order Intelligence unit (NPOIU) – which infiltrated political campaigns.

The Met has sent letters of apology to 15 families whose children died young, but in each case has neither confirmed nor denied whether identities were stolen.

The last case concerned a suspected spy, deployed between 1999 and 2003, who allegedly stole the identity of Rod Richardson, a boy who died two days after being born in 1973.

The family's lawyer, Jules Carey, said that Barbara Shaw, the mother of the dead boy, was taking legal action as she felt her complaint had been "swept under the carpet".

Carey said Hogan-Howe's apology was a PR exercise. He added: "The families of the dead children whose identities have been stolen by the undercover officers deserve better than this. They deserve an explanation, a personal apology. The harvesting of dead children's identities was only one manifestation of the rot at the heart of these undercover units."

Creedon said that the use of the technique "however morally repugnant, should not detract from the [spies'] bravery". He said that other undercover police units that penetrated serious criminal gangs in the 1970s and 1980s and possibly even the security services could also have used the tactic.