First-degree murder charges have been re-activated against Travis Vader in the case of two Alberta seniors who went missing during a motorhome expedition more than four years ago.

Vader, 42, was arrested “without incident” on Friday, after the Crown re-started proceedings against him, police said.

"He will appear to speak to these charges at Queen's Bench in Edmonton at a date yet to be determined,” RCMP said in a news release. “We will provide an update to that information when it becomes available."

Lyle and Marie McCann were last seen alive on July 3, 2010, as they fuelled their motorhome in St. Albert, located north of Edmonton.

In a brief statement Friday, the couple’s son, Bret McCann, asked that his family’s privacy be respected.

“Today's news means that we will now have the opportunity to learn more about the investigation into our parents death when this case comes to trial,” Bret McCann said.

“Our goal now is to ensure the accused receives a fair trial and to that end, we will not be speaking publicly at this time. We ask that you respect our privacy.”

The McCanns, both in their 70s, had been heading to visit family in British Columbia at the time of their disappearance.

Five days later, the McCann’s daughter reported them missing after they failed to show up in Abbottsford, B.C.

The torched remains of their motorhome, and the SUV they were towing, were later found west of Edmonton. Their bodies have never been found.

The two were declared dead by a court one year later.

Vader was originally charged with first-degree murder in April 2012.

But last March, just a few weeks before the trial was set to begin, the Crown stayed the first-degree murder charges against Vader.

When charges are stayed, the crown has one year to re-activate the case.

Vader filed lawsuits against prosecutors and the RCMP claiming malicious prosecution. He alleged he was kept in custody on trumped-up charges before he was charged with the McCanns’ murders. He also said he was mistreated by staff at the remand centre.

With files from The Canadian Press