Los Angeles, Sep 14 (IANS): A $100,000 reward has been offered for information leading to the arrest and conviction of a suspect who shot two Los Angeles County Sheriff's deputies, authorities said.

The reward was authorized on Sunday by the Los Angeles County Board of Supervisors for "a lone gunman", who is described as a black male between 28-30 years-old, wearing dark clothing, Xinhua news agency quoted the Los Angeles County Sheriff's Department (LASD) as saying in a statement.

Both deputies were shot late Saturday night in Compton, a city situated south of downtown Los Angeles.

The suspect approached the vehicle from behind and fired several rounds from his firearm.

The deputies sustained critical injuries, according to the LASD.

Los Angeles County Sheriff's Homicide investigators continued their probe to determine the circumstances surrounding the shooting

A video clip of the shooting posted online by the Sheriff's Department showed the suspect moving towards a sheriff's vehicle parked by the roadside and opening fire without warning or provocation.

The shooter then ran away from the scene.

"We at the LASD would like to offer our sincerest appreciation for the overwhelming support being offered from all over the Nation. We also wish to thank the LA County Board of Supervisors for sponsoring the 100,000-dollar reward for the arrest and conviction of this coward," said Los Angeles County Sheriff Alex Villanueva in the statement.

Villanueva said that the deputies "survived the shooting and (are) recovering, a double miracle" and detectives had been "working furiously overnight" to identify the shooter, The Los Angeles Times reported on Sunday.

One of the deputies is a 31-year-old mother of a six-year-old boy and the other is a 24-year-old man, said officials in a news briefing Saturday night.

President Donald Trump and Democratic presidential nominee Joe Biden have both condemned the attack.

California Governor Gavin Newsom called the attack a "cowardly, horrific act" and noted that "the perpetrator must be quickly brought to justice".

Mayor of Los Angeles Eric Garcetti also strongly condemned "this cowardly ambush" and sent prayers of healing to the deputies shot "in a horrific attack".