Police wey dey find di parents of three newborn babies, all abandoned in east London minutes afta dia birth, say dem now dey focus on about 400 nearby houses.
Dem bin leave Baby Elsa inside one Boots carrier bag near one footpath in Newham on 18 January 2024, bifor one dog walker discover am.
DNA tests later established that she was the sibling of two OD babies, one boy and one girl, each found for very similar circumstances in 2017 and 2019.
Despite say police dey beg, dem still never sabi di parents of di three babies.
For di last five weeks, detectives wey dey search for di parents don give BBC News access to part of dia operation.
Dem allow us to follow officers wey dey go door-to-door dey ask residents to provide DNA samples to see if dem get connection wit di babies.
Dem also dey contact pipo wey dem find say dey use di national DNA database wey fit share familiar DNA wit di children mama.
Officers wey bin recently meet Elsa bin tell BBC say di toddler na bright girl wey dey curious and engaging.
Na on 17 September 2017, wen dem bin find di first baby, Harry, dem find, over a mile to di west of di spot wia dem leave Elsa – just north of di Greenway, a four-mile long footpath and cycleway in Newham. Dem bin leave am for one bush in Plaistow Park, wrap am in towel.
Sixteen months later, dem discover im sister Roman ontop bench by one dog walker in di small children play park, for Roman Road.
Dem bin find her for one freezing evening, at about 22:15. Roman dey wrapped for towel, inside one Sainsbury shopping bag.
Di babies’ names dey given to dem by emergency staff wey bin help dem – dey all don dey changed since.
DNA tests bin show say Harry and Roman be full siblings, however, dat information bin no first dey public.
Na only wen dey find Elsa five years later, and di case come bifor family court, bifor we dey able to report say all three babies get same parents.
Det Insp Jamie Humm, wey become tdi case senior investigating officer afta Elsa dey found, say “No be huge shock” wen DNA bin confam say she be di sister of di oda two babies.
Elsa don dey abandoned just few minutes’ waka from wia dem find Roman.
For di first 12 months afta e take on di investigation, Det Insp Humm bin assume say di baby dem mama dey able to contact police, but dey reluctant to do so.
Im team bin search di area, knock on doors, tok to local pipo, but no-one don see or hear anytin.
In January dis year, di charity Crimestoppers bin offer a £20,000reward for information, wey also prove fruitless.
“Now my strong feeling na say [di mama] no dey able to come forward,” Det Insp Humm tok.
E believe say di babies’ mama fit dey restrained in some way – or she fit get mental or physical health problems.
Police don dey work closely wit experts from di National Crime Agency (NCA), as well as psychological and geographical profilers.
Dem assume say di mama bin leave di babies herself. Paediatric experts don advise say for war zones, for example, mothers don give birth den “get up and waka” immediately.
Police also believe say di mama sabi di local area well.
She bin avoid CCTV cameras and witnesses, yet place all di babies in locations wia dey fit likely dey found quickly.
Analysis of CCTV footage bin lead officers to rule out say di mama use car to get to di sites – instead dey believe say she bin waka along di Greenway.
Now CCTV don dey wia dem find Elsa, however, none bin dey for January 2024, wen she dey abandoned.
Det Supt Lewis Basford, wey don take on strategic oversight of di investigation, acknowledge say conventional techniques don fail to identify di parents so far.
Now, e say di Met dey put plenti emphasis on di investigation to open up new lines of enquiry.
To do dat, dem dey use DNA test, wey dey often dey use in homicides, like novel way.
First, dem don search di national database to find partial matches. Wey throw up many thousands of names. Dey don use oda information to focus on pipo wey fit dey related to di parents.
Det Insp Humm and im team dey focus on about 300 names, and dey plan to see dem all in pesin.
Wit Work wit di NCA, dey also don identify about 400 homes close to di eastern section of di Greenway, from wia di mama fit don waka wit a baby and avoid CCTV.
Dem dey cross-reference those addresses wit information from di electoral roll and oda agencies to find di most likely locations, for pesin wey fit dey connected wit di parents.
In teams of two, officers dey knock on doors to request DNA samples. Det Sgt Laurence Dight say dey generally dey receive warm response. Pipo don hear about di babies and wan help.
E say pipo often dey happy to take di test. Some no gree, wey dey within dia rights.
Once dey don collect samples, dey analyse dem, and decide on di next steps.
In di local community, many dey mystified. Di congregation of East Ham Baptist Church dey bring togeda pipo from all over di world.
Dey regularly dey hold prayers for di mother and babies. Pastor George Tikum, originally from Cameroon, say e dey possible di parents dey here illegally, and leave di babies sake of say dey get more secure life if adopted.
E say di mystery don turn many locals into amateur detectives.
“I still tink say di answer lie wit one pesin to come forward and just give those answers to Elsa and her siblings as to wetin happened to dem and why e happun,” Det Insp Humm tok.
Im concern na for di babies’ mother – and any future children. Officers describe di survival of di three newborns as “miraculous” and worry a fourth child fit no dey so fortunate.
Elsa now just be over one year old and dey toddle and bright.
Det Insp Humm say e bin meet her a couple of months ago, wit police colleagues. She dey “very curious” e tok “Very engaging. No fear.”
Hospital staff dey call her Elsa – wey dey found, only an hour old, on di coldest night of di year – afta di character in di Disney film Frozen.
Now in foster care, Elsa don make wetin family court judge Carol Atkinson call “astonishing progress”.
Det Insp Humm say wen officers recently meet her “everyone dey struggle to keep dia emotions in check”.
“Di one wey no be Elsa; she just be di happiest, coolest,” e tok. I think she’s going to make everyone proud—she’s going to make her mum proud as well.”

Police dey door-knock for one area near di Greenway, one open space wia Elsa dey found

Dem find baby Elsa inside one Boots bag on di Greenway, in Newham, east London

