A new suspect has been named in the racist murder of Black teenager Stephen Lawrence in southeast London over 30 years ago.

Matthew White, who died in 2021, was named by London's Metropolitan Police Service (Met) in a statement Monday which apologized for a "significant and regrettable error," that meant key information about White was not properly followed up on.

The statement, issued in response to a BBC investigation released Monday into the Met's mishandling of key inquiries, added that too many "mistakes" were made in the initial investigation of the murder.

Two men were sentenced to life in jail in 2012 for the murder, but "three or four other killers of Stephen Lawrence (are) at large," according to the statement from the Met's Deputy Assistant Commissioner Matt Ward.

Baroness Doreen Lawrence, Stephen's mother, told CNN there should be "serious sanctions" against police officers who failed properly to investigate the murder of her son.

"Only when police officers lose their jobs can the public have confidence that failure and incompetence will not be tolerated and that change will happen," she said.

Lawrence, an 18-year-old architecture student, was fatally stabbed at a bus stop by a gang of youths in April 1993. His friend, Duwayne Brooks, was also attacked but managed to escape.

Five teens were identified as being involved and were arrested, but none was successfully prosecuted at the time.

It took years of campaigning by Lawrence's family until an inquest into his death in 1997 found that he was unlawfully killed in a "completely unprovoked racist attack by five white youths."

Institutional racism uncovered

A wave of protests forced the then-government to commission an inquiry into the killing in 1999.

It found that the initial police investigation into the murder had been "marred by a combination of professional incompetence, institutional racism and a failure of leadership."

In their statement Monday, the police said they had previously misidentified a relative of White who held key information into the killing and apologized for the "significant and regrettable error."

The statement went on to outline how White was arrested twice, in 2000 and 2013, and stated that on both occasions prosecutors said there was no realistic prospect of conviction.

In February 2020, White was spoken to again by the investigation team but there was "insufficient witness or forensic evidence to progress further," the statement said. He died in August 2021, months before the police declared the murder investigation inactive and said there were no further lines of inquiry.

In May 2023, the Met commissioned a forensic review into the case.

Ward acknowledged in the Met's statement Monday that "the impact of the racist murder of Stephen Lawrence and attack on Duwayne Brooks, and subsequent inquiries, continues to be felt throughout policing."

He added: "On the 30th anniversary of Stephen's murder, Commissioner Sir Mark Rowley apologized for our failings and I repeat that apology today."

Baroness Lawrence told CNN: "What is infuriating about this latest revelation is that the man who is said to have led the murderous attack on my son has evaded justice because of police failures and yet not a single police officer has faced or will ever face action."

"It is too late for me and my family but at least I hope that victims in the future will not go through what we did," she added.