The Spanish Civil Guard confirmed that Jota and his brother were found dead near the northwestern city of Zamora.
Firefighters were called in as the fire spread into the nearby vegetation, authorities said.
Police were investigating the causes of the accident that happened past midnight local time. They said there were no other vehicles involved.
It wasn't clear who was driving the car. Police were looking into the hypothesis that the accident happened because of a blown tire.
The accident occurred while they were driving eastward along an isolated stretch of highway about an hour west of Zamora.
The 28-year-old Jota and his 25-year-old brother, both Portuguese players, were the only ones in the car, police said.
Jota's death comes days after he married Rute Cardoso and in a social media post wrote, "Yes to forever." They had three children, the youngest born last year.
Jota also played for Portugal's national team and helped them win the Nations League last month.
Silva played with Portuguese club Penafiel in the lower divisions.
Liverpool said the club was "devastated by the tragic passing."
"Liverpool FC will be making no further comment at this time and request the privacy of Diogo and Andre's family, friends, teammates and club staff is respected as they try to come to terms with an unimaginable loss. We will continue to provide them with our full support."
Jota joined Liverpool from Wolves in 2020 and won three major trophies with the Merseyside club - including the Premier League title last season.
The Portuguese soccer federation released a statement lamenting the deaths. Federation president Pedro Proença said Portuguese soccer was "completely devastated."
"More than a fantastic player, with almost 50 appearances for the national team, Diogo Jota was an extraordinary person, respected by all his colleagues and opponents. He had a contagious joy and was a reference in his community," Proença said in the statement.
"We lost two champions," Proença added. "Their deaths represent an irreparable loss for Portuguese soccer and we will all do our best to honor their legacy daily."
Portugal's Prime Minister Luís Montenegro commented on the "unexpected and tragic" deaths. He said Jota was "an athlete who greatly honored Portugal's name."
"I extend my deepest condolences to their family," he said. "It is a sad day for soccer and for national and international sports."
Reaction also started pouring in from across the world, including from non-soccer players such as NBA star Lebron James and tennis legend Rafael Nadal.
"It doesn't make any sense," Jota's Portugal teammate Cristiano Ronaldo said. "Just now we were together in the national team, just now you had gotten married. My condolences to your family, to your wife and to your children. I wish them all the strength in the world. I know that you will always be with them. Rest in peace, Diogo and André. We will all miss you."
The Premier League said it was "shocked and devastated."
"Our sincerest condolences go to Diogo's family, friends, Liverpool FC, and all their supporters at this heartbreaking time," it said. "Football has lost a champion who will be forever missed. We will continue to support our friends and colleagues at the club."
UEFA said its thoughts were with relatives, friends and teammates affected "by this heartbreaking loss." It said a moment of silence will be observed at Euro 2025 matches on Thursday and Friday.
with AP
