An illegal immigrant who ran down and killed an FBI agent and a fire marshal on the side of a highway has avoided jail.

Roberto Garza Palacios, 28, who arrived in the US in Guatemala and has overstayed his visa, paid just a $280 fine for killing Deputy Chief State Fire Marshal Sander Cohen and FBI Special Agent Carlos Wolff in December.

Garza Palacios did not appear in court and the case was closed on June 25 when he handed over the financial penalty, according to court documents obtained by the Washington Post.

Roberto Garza Palacios, 28, served no jail time for his role in the December crash that killed Deputy Chief State Fire Marshal Sander Cohen (left) and FBI Special Agent Carlos Wolff (right)

Wolff and Cohen were standing on the side of the road on I-270 in Montgomery County when they were struck by a Honda Accord driven by Garza Palacios. Wolff had crashed after reaching for his cellphone, and Cohen had stopped to help.

Driving up behind the scene, Garza Palacios told authorities that he couldn't swerve right and went left - not seeing the two men.

Cohen was hit by another car and died at the scene, while Wolff died at the hospital.

Wolff and Cohen were standing on the side of the road on I-270 in Montgomery County when they were struck by a Honda Accord driven by Garza Palacios

Prosecutors found that while Garza Palacios drove in a 'careless and imprudent manner,' he did not do so in a way that was a 'gross deviation' from driving carefully.

They couldn't find that Garza Palacios had a 'reckless disregard' for human life which would prompt more serious charges.

'This case is about an unfortunate accident. Mr. Garza Palacios feels terrible about the situation,' his attorney, Asim A. Humayun, said.

Prosecutors found that while Garza Palacios drove in a 'careless and imprudent manner,' he did not do so in a way that was a 'gross deviation' from driving carefully. They couldn't find that Garza Palacios had a 'reckless disregard' for human life which would prompt more serious charges

Garza Palacios, a native of Guatemala, still faces possible deportation.

On May 3, immigration authorities arrested him after the accident and charged him with overstaying a visa that expired in 2009.

In 2015, Garza Palacios was arrested in Montgomery County and ICE asked him to be placed on hold but that request was not honored.

Humayun stated that the immigration case is still ongoing.

Garza Palacios pleaded guilty to driving while impaired in 2015.

He served a four month stint in jail after smashing windows on 16 cars and lighting a sofa on fire near a construction site.