Footage has emerged of the Clapham suspect filmed a day before the chemical attack on a woman and two children.
In the footage obtained by Sky News, Abdul Ezedi can be seen looking for groceries and smiling in a shop in Newcastle.
Ezedi, 35, has been urged by police to hand himself in after going on the run following the attack involving a corrosive alkaline substance in Clapham, southwest London, on Wednesday 31 January.
The Metropolitan Police has launched a manhunt to find a man thought to have fled the scene, with help from the British Transport Police and Northumbria Police in Newcastle, where Ezedi lived.
A £20,000 reward is on offer for information leading to Ezedi's arrest, with police revealing the substance used in the attack was "very strong", "concentrated" and "corrosive".
The woman, who was known to Ezedi, remains in hospital in a critical but stable condition and may lose sight in her right eye, while her daughters - aged eight and three - have injuries not thought to be life-changing.
Investigators believe there are people who know his whereabouts and have not come forward and the Met has warned anyone found helping him will face arrest.
On Monday, a 22-year-old man was arrested on suspicion of assisting an offender and has since been bailed.
Police have also recovered Ezedi's mobile phone and are analysing it to establish the relationship between him and the victim.
Armed police were called to a false alarm at Manchester Piccadilly railway station on Saturday night, after reports of a sighting.
The search continues with investigators trawling through hundreds of hours of CCTV and tracking his movements via his bank card, with the latest sighting now on Southwark Bridge in London at 9.50pm on Wednesday.
Detectives are working on the premise that he is either being hidden by someone or has come to harm.
Police say Ezedi left Newcastle in the early hours of Wednesday and was in the Tooting area of London by around 6.30am.
His vehicle was seen again in Croydon, also in south London, at around 4.30pm and by around 7pm he was in Streatham.
Ezedi allegedly threw the younger child to the ground during the attack at 7.25pm, before trying to drive away from the scene, crashing into a stationary vehicle and fleeing on foot.
Minutes later he boarded a Tube train at Clapham South Underground station, and by 8pm he was at King's Cross Tube station.