Three Britons are among those killed in the earthquake which has devastated central Italy.

An official from the town of Amatrice, one of the worst affected areas, told the Press Association that the British nationals were among the dead.

Two of the victims are believed to have owned an apartment in Sommati, a village about 1.3 miles from Amatrice, according to Sky News.

The other is understood to be the teenage son of another family who were staying with the owners.

Sky News said the apartment owners' two children survived but their condition was unknown. The mother and father of the other family are in hospital and their daughter also survived. Her condition is unknown.

The Daily Mirror said the mother and father had initially been taken to separate hospitals 40 miles from each other, where the woman was being treated for facial fractures and the man was being treated for a broken leg.

Rieti Hospital director Pasquale Carducci, told the newspaper: "The British woman was brought here by rescue workers on Wednesday while her husband was taken to L'Aquila.

"When we discovered he was there we decided they would be happier together, so we decided to reunite them.

"Since the man was less badly hurt it was easier to bring him to her. We hope that they can be a support to each other."

Foreign Secretary Boris Johnson said on Thursday that a number of Britons had been "affected" by the earthquake, which has left at least 250 people dead and levelled three small towns after it struck in the early hours of Wednesday.

Mr Johnson said extra staff had been sent to the region to help provide support to Britons affected by the "terrible" quake, 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."

Aftershocks have been felt in central Italy as rescue workers continued efforts to find survivors. At least 365 people were injured in the initial earthquake and the aftermath.

A day after the shallow quake levelled three small towns, a 4.3 magnitude aftershock hit the already-devastated settlement of Amatrice.

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.