Two more men have been arrested over the deaths of a mother and her four-year-old son in a house fire.
Gina Ingles, 34, and her son Milo Ingles-Bailey died after an arson attack in Croxden Way, Eastbourne in July last year.
Ms Ingles’ partner Toby Jarrett, 27, was also in the house at the time of the fire, but managed to escape through a first floor window.
He sustained serious burn injuries and was taken to hospital for treatment.
Sussex Police said officers arrested two men – a 41-year-old man from Hastings on suspicion of murder and a 27-year-old man from Eastbourne on suspicion of conspiracy to murder – on Tuesday.
Both were later released under investigation.
Police have also interviewed a third man in Portugal in connection with the blaze.
A police spokesman said: “Detectives from the Major Crime Team also travelled to Portugal during the week and, with the assistance of the Portuguese authorities, interviewed a further suspect who is already in prison in Portugal for an unrelated offence.”
Detectives have also issued CCTV footage of two individuals who they say hold “vital information” about the fire.
Detective Inspector Gordon Denslow said: “The Surrey and Sussex Major Crime Team continues to pursue those responsible for this horrific crime, and will do so relentlessly on behalf of Gina and Milo’s family, who continue to grieve for the loss of their daughter and grandson.
“This is a significant development in this investigation. In addition to these arrests, we have also interviewed a number of other people who we think may know something about what happened on that tragic day in July 2018, and they are helping us with our enquiries.
“We are working closely with the Portuguese authorities, and will release further information when we are able to.
“I’d like to thank the community for their continued support, and encourage anyone with any information at all to please come forward. Help us find out who is responsible for the death of a vulnerable four-year-old boy and his young mother.”
Two local men, aged 23 and 47, were previously arrested on suspicion of two counts of murder and one of attempted murder.
The 23-year-old remains released under investigation pending further enquiries while the 47-year-old was released without charge and will face no further action.