Hallowell police on Thursday pulled the plug on efforts to enlighten Gov. Janet Mills about the dangers of data centers.

Police Chief Christopher Giles said officers cited the driver of a mobile, electronic billboard urging Mills to sign a bill that would institute a moratorium on data centers.

Giles said the driver was pulled over for speeding on Water Street after an officer clocked him doing 38 in a 30 mph zone. He was subsequently charged with displaying an illuminated advertisement on a vehicle, which is against the law and subject to a $152 fine.

Giles said the vehicle is owned by Guerrilla Mobile Billboards, of Topsfield, Massachusetts.

After this story was initially published online, the civil society group Ekō took responsibility for the billboards.

“AI data centers are being sold as economic opportunities, but the reality is higher bills, environmental strain, and very few permanent jobs,” said Ekō Campaign Director Deborah Lewis in a statement that did not address the incident with police. “Maine has a chance to draw a line and protect its communities before the damage is locked in.”

The billboards featured Mills’ image with messages opposing data centers on three sides of a black box truck.

Lawmakers on Tuesday passed a bill to enact a one-year moratorium on data centers, which have drawn scrutiny across the country because they consume large amounts of energy and water. The moratorium would the first of its kind in the nation.

Mills has not indicated whether she will sign the bill, but she has expressed disappointment that the proposal was not changed to allow a data center to be built at an old paper mill in Jay.

“Jay needs those jobs, with appropriate guardrails for conserving water resources, electricity resources,” she said at a budget-signing ceremony in Bangor last week, according to the Bangor Daily News.

One of the billboard’s messages said that “65% of Americans oppose new data centers,” while another said, “Maine voters don’t want rising energy costs. Governor Mills: Pass the AI Data Center moratorium.”

The third image said data centers only create temporary jobs rather than long-term ones.

The bill, LD 307, would create a limitation on data centers with electric loads of at least 20 megawatts by preventing the state, local governments and quasi-governmental agencies from issuing permits or other approvals until November 2027.

In the meantime, a new Data Center Coordination Council — also created in the bill — would get time to study the centers’ potential impact in Maine and issue policy recommendations.

Mills has until April 25 to sign, veto or allow the bill to become law without her signature.