Kansas City Chiefs assistant coach Britt Reid will miss the Super Bowl after he was placed under investigation following a traffic accident that left a five-year-old child with life-threatening injuries.

Reid, the son of Chiefs head coach Andy Reid, remained in Kansas City on Saturday as the team travelled to Florida for Sunday’s NFL showpiece against the Tampa Bay Buccaneers, the Chiefs confirmed.

The 35-year-old linebackers coach, who has a history of drink and drug problems, is being probed for driving while impaired following Thursday’s multi-vehicle accident that left two children injured, one seriously.

Reid, who was given an eight-to-23-month prison sentence in 2007 for a road rage incident in which he threatened a motorist with a gun, told police at the scene he had been drinking before the crash.

A search warrant filed by the Kansas City Missouri Police Department said Reid showed “signs of impairment” following the accident.

A police officer at the scene said Reid had bloodshot eyes and admitted having had “two or three” drinks earlier in the evening. A blood sample had been taken to determine Reid’s level of impairment, the warrant showed.

No further information has been released by Kansas City police, while the Chiefs have not commented beyond confirming that Reid was involved in a multi-vehicle accident.

Reid’s truck is alleged to have struck two cars parked on the edge of a motorway near the Chiefs’ training complex in Kansas City.

One of the cars had run out of fuel and the driver called a relative who drove to the scene with two children strapped into the back seat of the car. Reid’s truck hit both parked cars, seriously injuring one of the children.

The incident is the latest episode in a troubled family history for Chiefs head coach Andy Reid.

His eldest son, Garrett Reid, died of an accidental heroin overdose in 2012 during a Philadelphia Eagles training camp.

Garrett Reid had also been involved in brushes with the law, arrested in January 2007 for drugs violations.

Britt Reid, meanwhile, who was arrested for road rage in 2007 on the same day as his brother’s arrest on drugs charges, eventually served six months in prison following his sentencing.

He entered rehab following his release on parole, and began a coaching career under the eye of his father, joining the Chiefs in 2013.

Meanwhile, there was little sign that Britt Reid’s arrest had disrupted Kansas City’s Super Bowl preparations on Saturday.

The team conducted an early morning walkthrough before travelling to Tampa on an afternoon flight.

“Good energy,” head coach Andy Reid told a pool reporter.

“It’s important to have that. This was just kind of a review day, so we go back through all the situations and make sure we have all those covered.”