A Weston woman was arrested for driving under the influence, risk of injury to a minor, possession of marijuana, possession of drug paraphernalia, and possession of narcotics on Nod Hill Road around 7 p.m. Wednesday, July 31.

Ridgefield police said Junyuan Tsai, 36, was found in possession of marijuana and a substance that was “suspected heroin,” according to a police report.

Capt. Shawn Platt confirmed that the substance tested positive as heroin on Tuesday, Aug. 6.

Police said that a caller reported a suspicious vehicle in the area of Nod Hill Road with right side damage.

The car was pulled over and an investigation revealed Tsai was under the influence of “alcohol and/or drugs,” the report said.

Tsai was charged with risk of injury to a minor because her child was in the backseat of the vehicle at the time of the traffic stop, Ridgefield police said.

Tsai was processed and released on a $1,000 bond. She is scheduled to appear in court Aug. 14.