The National Transportation Safety Board has found that a pickup driver’s drug use was the reason for a crash that killed seven New Hampshire motorcyclists.

The board on Tuesday unanimously approved a report that determined that Volodymyr Zhukovskyy’s impairment from the drugs was the “probable cause” for him crossing the center line on a rural highway in June 2019.

Investigators told the board he had drugs in his system and likely hit the motorcyclists because he was impaired. Documents show he told authorities he used heroin and cocaine.

He pleaded not guilty to negligent homicide.

His lawyer didn’t immediately comment Tuesday.