A 14-year-old boy on holiday with his parents is among three Britons killed in the deadly earthquake that rocked central Italy.

A married couple from south London also died following the 6.2 magnitude quake that struck early on Wednesday morning, which left 250 people dead and levelled three small towns.

Their devastated families paid tribute to "the tireless work of the Italian rescue workers and hospital staff" as the Queen made a donation to support search and rescue efforts.

A joint statement from their families issued by the Foreign Office said: "It is with sadness that we can confirm the deaths of Maria, 51, and Will, 55, Henniker-Gotley and Marcos Burnett, 14, in the earthquake in Amatrice, Italy on August 24.

"Their families have paid tribute to the tireless work of the Italian rescue workers and hospital staff and expressed their gratitude for the love and support they have received from the Italian people. Their thoughts and prayers are with all those affected by the earthquake."

The Foreign Office was providing support to the families, it added.

A state of emergency has been declared in the areas affected and aftershocks have continued to strike, including one of a preliminary magnitude of 4.7 on Friday morning.

The Queen donated an unspecified amount to the British Red Cross, of which she is a patron, to support the Italian Red Cross in its relief efforts, Buckingham Palace said.

The Queen and the Duke of Edinburgh have previously said they were "saddened to hear of the loss of life" and sent their "thoughts and prayers" to the "people of Italy, especially the family and friends of those affected".

Cornwall-based charity Shelterbox has sent a team over to Italy to assist with setting up accommodation for those displaced by the earthquake, while the British Red Cross has set up a section on its website for donations to be sent to their Italian counterparts.

Celebrity chef Jamie Oliver, meanwhile, announced that for a month £2 from each Pasta Amatriciana dish sold at his restaurant will be sent to help relief efforts.

It is believed Mr and Mrs Henniker-Gotley owned a property in Sommati, a village about 1.3 miles (2km) from Amatrice.

Their two children, believed to be aged 12 and 14, survived but their condition is unknown.

A neighbour, who did not want to be named, said: "They were lovely. They were a lovely family. It's very hard to take in.

"They were very warm and friendly, extremely good neighbours. It's just so awful to think of their children."

She added: "I think Maria's father came from the village and was possibly born there. When he was ill - he has since died - they bought a house there and they go out every summer."

Marcos and his family were staying with the Henniker-Gotleys.

His parents, Anne-Louise and Simon Burnett, were both taken to hospital and their daughter also survived. Her condition is unknown.

The mother and father were initially taken to separate hospitals 40 miles (60km) from each other, where she was treated for facial fractures and he was being treated for a broken leg.

The latest aftershock hit the region at 6.28am local time on Friday. The US Geological Survey said it had a preliminary magnitude of 4.7.

Italy's national geological institute put the magnitude at 4.8. It was preceded by more than a dozen weaker aftershocks overnight and followed by another nine in the subsequent hour.

The quake zone has experienced more than 500 aftershocks, some measuring 5.1, in the two days since the original pre-dawn quake on Wednesday.

Foreign Secretary Boris Johnson said on Thursday that a number of Britons had been "affected" by the earthquake.

He said extra staff had been sent to the region to help provide support to Britons, while the Government has offered "any assistance that we can" to the Italian authorities.

He said: "My deepest sympathies are with the Italian people and everyone affected by the terrible earthquake that struck central Italy.

"The British Government has offered any assistance that we can to help with the recovery effort and I have spoken with Italian Foreign Minister Paolo Gentiloni to express my condolences personally.

"As the scale of the disaster has become clearer, we now know that a number of British nationals have been affected.

"British embassy staff are in the region providing consular support, and we have deployed additional staff to support this effort."

Firefighters and rescue crews using sniffer dogs have been working in teams around the hardest-hit areas of the country.

"We will work relentlessly until the last person is found, and make sure no-one is trapped," said Lorenzo Botti, a rescue team spokesman.