The son of a couple missing from St. Albert since July 2010 “remains optimistic” that a new push by RCMP for clues in the case will lead to more details on his parents’ fate.

Bret McCann said he’s known the RCMP have been looking to speak with a welder who modified the senior McCanns’ SUV so they could tow it behind their RV, but he doesn’t know why.

On Thursday, the RCMP asked for public help in finding the worker who altered a tow bar to fit Lyle and Marie McCann’s 2006 Hyundai Tucson.

The tow bar had been mounted on Lyle’s 1988 Dodge RAM pickup, but was later altered and installed on the SUV, police said.

“I can tell you this isn’t the break in the case, it’s just a piece of the puzzle,” RCMP Sgt. Tim Taniguchi said.

Bret McCann said he is resigned to the fact that his mother and father are gone, but he wants closure.

“We really need to know what happened to my parents and police are fully with us on that,” he said.