An electric bus fleet promoted by prominent Democrats including Connecticut Democratic Sen. Chris Murphy and Gov. Ned Lamont is being pulled from service following a large lithium battery fire that engulfed a bus on Saturday, according to CT Insider.

An unoccupied CT Transit electric bus was incinerated after its lithium battery caught fire in the parking lot of the transit department, according to Hamden Fire Department officials who were called to put out the fire. Following the incident, CT Transit, the state’s bus service, pulled the electric bus fleet, which was promoted by the Democrats, from service, CT Insider reported.

The electric buses will not be redeployed until an investigation into the battery fire is completed as a public safety precaution, according to CT Transit spokesperson Josh Rickman. The transit authority deployed diesel buses to replace the electric buses to continue its transportation service.

“Lithium-ion battery fires are difficult to extinguish due to the thermal chemical process that produces great heat and continually reignites,” said the Hamden Fire Department.

Murphy announced his support for the transit department’s electric buses in a tweet posted in March, praising an $11.4 million federal grant aimed at curbing public transport’s carbon emissions. Murphy said that the buses would help break America’s “dependence” on foreign oil.

Lamont also praised a $7.4 million federal grant that helped the state purchase 10 electric buses in a 2o21 press release, claiming that the buses would help curb carbon emissions and promote a healthier future. The state’s transportation department also received a similar $6.7 million grant in 2020 to procure electric buses and modernize its bus maintenance facility.

“They’re quieter, they emit no emissions and they last longer,” State Department of Transportation Commissioner Joe Giulietti said of the buses on Friday, according to CT Insider.

The bus was produced by Minnesota manufacturer New Flyer and the state was awaiting the delivery of 10 more buses in the coming months, a source familiar with the situation told the Daily Caller News Foundation.

“New Flyer is working closely with CT Transit and the Connecticut Department of Transportation to investigate this highly unusual event and have deployed our field service team to the area,” New Flyer said in a statement provided to the DCNF.

“New Flyer buses are engineered, manufactured, innovated, and rigorously tested to be among the safest vehicles in North America, and the most reliable form of public transit in communities,” the statement continued.

The buses are nearly double the cost of regular diesel buses, even before charging infrastructure expenses are taken into account, according to The New Haven Independent. The project to replace diesel buses with electric buses will also cost about $25.7 million in total, the NHI reported.

Murphy, the Hampden Fire Department and New Flyer did not immediately respond to the DCNF’s request for comment. CT Transit also did not immediately respond to the DCNF’s request for comment.