A brother of one-time leading Democratic presidential candidate Senator Elizabeth Warren has died from the coronavirus.

Ms Warren said her brother, Donald Reed Herring, died Tuesday evening. He 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 that Mr Reed, 86, died in Norman, Oklahoma, about three weeks after testing positive for the virus.

He flew B-47 and B-52 bombers for the Air Force, and flew 288 combat missions in Vietnam. 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,” Ms Warren said.

Ms Warren, 70, was once among the frontrunners for the 2020 Democratic nomination, regarded a serious challenger to the likes of Joe Biden and Bernie Sanders. She was renowned for her personal energy, often bounding out onto stage at rallies.

Her race petered out in early primary contests and she has since endorsed Mr Biden.