RCMP have charged a 61-year-man over several large-scale thefts of oil from energy sites in Saskatchewan and Alberta.

Mounties said they made an arrest Tuesday following an investigation that spanned several months.

The accused is from Lashburn, Sask., and is facing seven counts of theft over $5,000.

RCMP said a tanker truck that can carry 30 cubic metres of oil was used to commit the alleged thefts.

The benchmark price for oil is now under $30 US per barrel, leading to questions about why someone would steal oil.

"I don't know, I guess that's something we'll have to ask the suspect involved," Sgt.  Jolyne Harrison, from the Maidstone detachment of the RCMP, said Thursday. "I guess there is still some profit to be made."

Harrison added the charges are rare.

"Mostly because it's hard to prove," Harrison said. "There's no identifiable features in oil [so] it's not as easy to prove that it belongs in a specific area."

RCMP said the thefts were noted around Maidstone and Cutknife in Saskatchewan and around Kitscoty in Alberta. Thefts were also noted around Lloydminster, the community that straddles the Saskatchewan-Alberta boundary.

The accused is set to appear in court on Feb. 23.