A driver who crashed his car into pedestrians on the sidewalk in New York City’s Times Square on Thursday morning tested positive for synthetic marijuana, multiple outlets are reporting.

Richard Rojas, 26, lost control of his vehicle just before noon on Thursday. His vehicle hopped the curb, killing one, 18-year-old Alyssa Elsman, and injuring 22, the New York City Police Department confirmed. 

Rojas reportedly tested positive for synthetic marijuana, otherwise known as spice or K2, after he was brought into police custody. 

NYPD officials declined to confirm the report to Business Insider, and would only say their “investigation is ongoing.”

Rojas, a Bronx resident and Navy veteran, was previously arrested for a DUI in 2008 and 2015, reports Pix11. He was also reportedly charged with menacing earlier this month. 

Synthetic marijuana is a lab-produced, mind-altering drug that’s been soaring in popularity in recent years. It’s illegal to purchase and consume in New York state. 

Giant underground laboratories, many of which are in China, are churning out thousands of pounds of the stuff. This week, the DEA arrested a man whose lab likely produced the chemicals in some 70% of the spice sold in the US, the New York Times reports.

Although it’s often marketed as a “safer alternative to traditional marijuana,” spice is dangerous — it’s been reported to cause seizures, psychosis, and vomiting, among other side effects.