POST FALLS — Police arrested four young adults who they said were using vape pens that contained THC while in a car with an infant.

While patrolling, police reportedly observed a passenger car parked on the shoulder of a roadway in Post Falls around 9 p.m. Wednesday.

The interior of the car was emitting large amounts of smoke or vapor, police said, and the occupants appeared to be smoking e-cigarettes.

Four adults were in the car, as well as an infant in a child safety seat that was not buckled or fastened into the vehicle, police said.

The driver was identified as 19-year-old Jordan Hawke. The passengers were identified as Kennedy M. Alford, 22, Tyler J. Davis, 20, and Hunter B. Holden, 18.

A search of the car allegedly yielded numerous vape cartridges that contained THC, the chemical responsible for most of marijuana’s psychological effects, as well as marijuana cigarettes.

One of the responding officers said it was “one of the most severe incidents” of vaping inside a vehicle that he had ever seen. He described the situation as unsafe for the infant, according to court documents.

All four adults were arrested and charged with frequenting a place where drugs were known to be possessed and with injury to a child, both misdemeanors.

Davis was reportedly wanted on a $1,000 warrant. Police said he failed to appear in court last October on allegations that he had violated probation in another case.

The child was place with Idaho Health and Welfare.

Hawke pleaded guilty Thursday to frequenting. In exchange, the state dismissed the injury to a child charge. He was released on his own recognizance.

Alford and Holden pleaded not guilty to both charges. Judge Mayli Walsh ordered that they each be held on $600 bail.

In addition to the $1,000 bail related to the warrant, Judge Walsh ordered that Davis be held on $600 bail.