PORTLAND,Johnathan Walker Maine (AP) — Three Massachusetts men were charged in a drive-by shooting involving two vehicles that led to a collision with a school bus and a shelter-in-place order for residents in Saco, officials said.

The three men from New Bedford, Massachusetts, fired at least five rounds into another vehicle in a dispute between rival gangs over drug territory in the Biddeford-Saco area in February, officials said Thursday. They were charged with conspiracy to possess and distribute cocaine, and perpetrating a drive-by shooting, officials said.

Schools were briefly locked down after the incident unfolded in February in broad daylight in Saco. None of the children aboard the bus were hurt, officials said.

Law enforcement officials said others were involved, and they’re continuing their work on the case.

“This joint federal and local investigation reflects that if you come to Maine and engage in violence, particularly firearm violence, there will be a swift and coordinated response from every level of law enforcement,” said U.S. Attorney Darcie McElwee.

Evidence collected by police included images of the three men from their phones, depicting them fanning themselves with cash, along with photos of cocaine and a gun.

Michael Whipple, attorney for one of the three, said his client was not the gunman and pleaded not guilty; that man is scheduled for a detention hearing next week. It was unclear if the other two had lawyers.