Police have been searching an area of the River Thames in central London for alkali attack suspect Abdul Ezedi.
A police boat circled between Vauxhall and Chelsea bridges, flashing lights and pausing beside a small ship before moving off again on Saturday morning.
Detectives believe Ezedi may have gone into the river after being seen on CCTV leaning over the railings of Chelsea Bridge in west London on the night a woman and two young girls were attacked with a corrosive substance in Clapham, south London.
The force said on Friday its main working hypothesis was the 35-year-old had “gone into” the Thames.
However, police admit that Ezedi’s body may never be found due to the speed of the current in the river.
“We have looked at all of the available cameras and angles, and with the assistance of Transport for London and CCTV from buses that were travelling over the bridge at the relevant time and there is no sighting of him coming off the bridge.”
Asked whether police were willing to say that Ezedi was dead, Detective Superintendent Rick Sewart said: “I’m prepared to say that he’s gone into the water and if he’s gone into the water then that’s the most probable outcome.”
The breakdown of the relationship is considered a possible motive for the attack.
Mr Savell confirmed the woman remained in a “critical but stable condition” in hospital and was still “very poorly and unable to speak” to police.
“It is quite likely that if he has gone in the water, he won’t appear for maybe up to a month and it’s not beyond possibility that he may never actually surface.”
Mr Sewart said the Met had tracked Ezedi’s movements from the Tower Hill area, where he has walked more than four miles “with purpose” to Chelsea Bridge.
“Then he walked to and from the side of the bridge and can be seen to sort of lean over the railings before there is a loss of sight.”
Earlier this week police said the last confirmed sighting was just before 11.30pm on January 31, a few hours after the attack, as he crossed over Chelsea Bridge and entered Battersea Park in central London, then crossed back over the same bridge minutes later.
The manhunt has been under way for more than a week, with officers raiding two addresses linked to Ezedi in Newcastle in the early hours of Thursday.
Ezedi, who is not the father of the children who were hurt, suffered significant facial injuries in the incident which police previously said could prove fatal if left untreated.