A town in the US state of Colorado has been left without any police after the entire department quit in one day.

The resignation of police marshal Tim Bradley prompted the town’s three other volunteer officers to do the same – leaving nearby El Paso County and Teller County sheriff’s offices to look after the town of Green Mountain Falls.

Residents were apparently offered no explanation for the sudden departure of their police force, although Fox News reported an anonymous source as saying the police were unhappy with the newly elected mayor Jane Newberry. Their resignations happened just a day before she took office.

Ms Newberry told the news channel: “In an election year there’s always some people who choose to stay and some people who choose to go and I think that happens at every level of government.

“He [the marshal] is pursuing other opportunities as I understand and good luck to him but that’s not to say that we are without police coverage."

At a town meeting, local people were told of the officers' decision to quit and a notice was also displayed at a local post office – but it was unclear when they would be replaced. It is believed the new mayor will advertise for new police officers as soon as the town’s budgets are decided.

“They [the residents] should absolutely feel safe,” Ms Newberry said. “I have every confidence in El Paso County Sheriff’s Office.