Four men arrested by police following an explosion outside the Women's Hospital in Liverpool on Sunday have been released without charge.
The news came after police named the suspected terrorist bomber who died in the explosion.
Although enquiries are ongoing, police said they 'strongly believe' he is 32-year-old Emad Al Swealmeen.
READ MORE: Terror suspect killed in Liverpool hospital explosion named by police
Nothing further about him has been released but police said he has been connected to two addresses currently being searched.
'Significant items' were recovered from one of the addresses - a property Al Swealmeen is believed to have only recently rented.
Tonight Assistant Chief Constable Russ Jackson said that police were satisfied with the accounts the four arrested men gave during police interviews.
He also said that officers had recovered important evidence from the address at Rutland Avenue which is becoming central to the investigation.
In a statement ACC Jackson said: "Following interviews with the arrested men, we are satisfied with the accounts they have provided and they have been released from police custody.
"The investigation continues to move at a fast pace with investigative teams working throughout the night.
"We have made significant progress since Sunday morning and have a much greater understanding of the component parts of the device, how they were obtained and how the parts are likely to have been assembled. We have also recovered important evidence from the address at Rutland Avenue which is becoming central to the investigation.
"There is a considerable way to go to understand how this incident was planned, prepared for and how it happened. We are gaining a better understanding by the hour but it is likely to be some time, perhaps many weeks until we are confident on our understanding of what has taken place.
"In the meantime, we have considerable resources and staff deployed to understand how this device was built and who if anyone else was involved. If the evidence takes us to the involvement of others, further arrests will quickly take place."
Earlier police urged the public to come forward with any details about Emad Al Swealmeen's life - 'no matter how small they may be'.
Det Chief Insp Meeks said: "We continue to appeal for any information about this incident and now that we have released his name any information that the public may have about Al Swealmeen no matter how small may be of great assistance to us.'
"Anyone who has any information should call on 0161 856 1027 quoting Liverpool Women's Hospital incident."
The news came as police confirmed a controlled explosion was carried out in a public park this afternoon.
The explosion inside a taxi outside Liverpool Women's Hospital just before 11am on Remembrance Sunday has been declared a terrorist attack.
Emergency services were on the scene within minutes and one man, the passenger in the taxi, was pronounced dead.
The driver of the taxi, named locally as David Perry, was injured but managed to escape and has since been released from hospital.
