A bipartisan group of U.S. senators is calling for an investigation into the death of Cuban dissident Oswaldo Payá after a car wreck in Cuba last year.

The Cuban government characterized the wreck as the result of careless driving. But others claim that a second car intentionally rammed the one carrying Payá, and another activist, Harold Cepero, who also died. They believe the Cuban government, which reportedly routinely harassed Payá as well as other dissidents, was behind his death.

On Monday, the senators, who include Florida Republican Marco Rubio and New Jersey Democrat Robert Menendez, both sons of Cuban immigrants, signed a letter to the Inter-American Commission on Human Rights of the Organization of American States asking for an investigation.

“Oswaldo Payá was a brave man trying to peacefully advocate for greater political freedom for his fellow Cuban brothers and sisters,” the letter said. “It increasingly looks like he paid for that effort with his life. His memory and his family deserve an honest and independent accounting of what happened. We urge the Commission to undertake this investigation without delay.”

Oswaldo Payá was a brave man trying to peacefully advocate for greater political freedom for his fellow Cuban brothers and sisters. It increasingly looks like he paid for that effort with his life. His memory and his family deserve an honest and independent accounting of what happened.

- Letter by bipartisan U.S. Senate group asking for investigation

The Cuban government said that Payá died after the car in which he was a passenger skidded into a tree after speeding. Cuban authorities placed the blame on the driver, Angel Carromero, an official of Spain’s Popular Party.

The authorities convicted Carromero, but released him in December, allowing him to serve the rest of his sentence in Spain.

But Carromero was quoted in an interview with The Washington Post earlier this month alleging that a car with Cuban government license plates deliberately hit their car.

Carromero told the Post that a car traveling behind them “began to harass us, getting very close.”

He said: “Oswaldo and Harold told me it must be from ‘la comunista’ because it had a blue license plate, which they said is what the government uses. Every so often I looked at it through the rearview mirror and could see both occupants of the car staring at us aggressively ... Suddenly I felt a thunderous impact from behind.”

In recent weeks, calls have grown louder for an investigation.

Payá’s daughter, Rosa María Payá, appeared before the UN Human Rights Council in Geneva a few weeks ago and delivered a petition with dozens of signatures of human rights activists and political leaders from around the world seeking an independent investigation of her father’s death.

Payá rose to international prominence in 2002, when he launched the Varela Project, a petition drive that generated more than 10,000 signatures calling for liberty in Cuba.

Payá received awards from numerous human rights organizations from around the world.

"We have confirmed that there was no accident," said Rosa Payá earlier this month. "We have a right to know how they died and who is responsible for their deaths."

Elizabeth Llorente can be reached elizabeth.llorente@foxnewslatino.com

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