Larochelle was last seen around 2:00 a.m. Dec. 21 near Desert Foothills and Charleston driving a tan 1998 Land Rover with a Nevada license plate 592-JBV, police said.
The Las Vegas Metropolitan Police Department has asked for the public’s help.
The department also asked hospitals to check registries and inform them if Larochelle is located.
Other details about the disappearance were not disclosed.
LaRochelle had been transferred from the northeast area patrol sector, police spokeswoman Laura Meltzer told the Las Vegas Review-Journal.
Las Vegas police described him as “endangered,” the paper reported.