Dalton Hoath described the children, named by family members as Kyson and Bryson, aged four, and Leyton and Logan, aged three, as "bright, caring, loveable boys".

The children died after a blaze ripped through a mid-terrace house in Sutton, south London shortly before 7pm on Thursday.

A 27-year-old woman who was arrested on suspicion of child neglect has been bailed.

The Metropolitan Police has said she will return to a south London police station in mid-January.

Mr Hoath, said in a statement given to MailOnline on Friday: "Myself and my family are utterly devastated by this tragic loss.

"They were bright, caring, loveable boys, but most of all Sons, Brothers, Grandsons, Great Grandsons, Nephews and Cousins.

"We would like to thank all the emergency services who did so much to try and save our boys, and also the local community who have come together at this difficult time.

"I would ask that my family are given time to grieve in private.

"They will be forever in my heart and thoughts, love Dad."

Chief Superintendent Dave Stringer, borough commander for Croydon, Bromley and Sutton Police, confirmed that the children were related.

He confirmed there was nobody else inside the property at the time of the fire.

The woman arrested on Thursday night on suspicion of child neglect remains in police custody, the police chief said.

In a post on Facebook, Jason Hoath wrote: "I am devastated to say that the horrendous house fire that took place in Sutton last night leading to four children loosing (sic) their life's (sic) were my amazing smart and beautiful grandsons.

"(They were) taken too soon they will always be in our hearts and thoughts.

"Boys I love you forever. Grandad xxx"