The oldest brother of US senator Elizabeth Warren, Donald Reed Herring, has died from coronavirus.

Key points: Donald Reed Herring joined the Air Force at the age of 19 and rose to the rank of lieutenant colonel

Donald Reed Herring joined the Air Force at the age of 19 and rose to the rank of lieutenant colonel Elizabeth Warren said her brother's smile "lit up everyone around him"

Elizabeth Warren said her brother's smile "lit up everyone around him" Ms Warren has formally backed Joe Biden in the presidential race, and is in the running to be his vice-president pick

The former Democratic presidential candidate said her brother died on Tuesday evening (local time).

Mr Herring spent his career in the military after joining the US Air Force at the age of 19 and was "charming and funny, a natural leader", Ms Warren tweeted.

"I'm grateful to the nurses and frontline staff who took care of him, but it's hard to know that there was no family to hold his hand or to say 'I love you' one more time — and no funeral for those of us who loved him to hold each other close. I'll miss you dearly my brother," she said.

The Boston Globe reported Mr Herring, 86, died in Norman, Oklahoma, about three weeks after testing positive for the virus.

Mr Herring flew B-47 and B-52 bombers for the Air Force, and flew 288 combat missions in Vietnam, the newspaper reported. He served as a B-52 squadron pilot and a squadron aircraft commander before retiring in 1973 as a lieutenant colonel.

"What made him extra special was his smile—quick and crooked, it always seemed to generate its own light, one that lit up everyone around him," Warren said.

The Boston Globe said Mr Herring had been living in a care facility for the last few months after being hospitalised with pneumonia.

It said he tested positive for COVID-19 in early April and started showing symptoms on April 15, at which point he was moved to intensive care.

He died six days later.

Ms Warren is said to be in the running for selection as presidential candidate Joe Biden's running mate in November's election.

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She formally backed Mr Biden earlier this week, saying "we can't afford to let Donald Trump continue to endanger the lives and livelihoods of every American" in a video announcing her decision.

More than 49,000 people have died from COVID-19 in the US, with more than 850,000 confirmed cases, according to Johns Hopkins University.

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