Quebec provincial police will significantly hike the number of officers assigned to its cold-case squad in the coming months as it aims to tackle a backlog of unsolved suspicious deaths dating back more than 50 years.

The unit's membership will increase from five to nearly 30 and will have a presence in the Montreal area and Quebec City, a spokesperson for the Sûreté du Québec said Monday.

Lt. Martine Asselin explained that regular investigators often have to respond to breaking crimes or urgent cases, meaning unresolved killings are relegated to the back burner.

That will change with a beefed-up staff committed solely to those unresolved cases.

"Now they will work full-time on these cases,'' Asselin said.

The unit will have plenty of work, as there are currently about 750 unsolved cases in its jurisdiction, dating back to the 1960s.

Nearly two-thirds are organized crime cases, however, the unit will focus on those suspicious deaths involving women, children and the elderly, Asselin said.

All Canadian police forces handle cold cases differently: some have a handful of police officers dedicated to the cases, while others leave it up to homicide detectives alone.

The SQ, which will have among the largest units, says it's found benefits in having a bigger group working on a case — such as in its investigation of the high-profile disappearance of Cédrika Provencher, a nine-year-old who vanished close to her home in Trois-Rivières in 2007.

In December 2015, Cédrika's remains were discovered in a wooded area and, to date, there have been no arrests in her disappearance and slaying.

Finding answers for families

When the squad was founded in 2004, it wanted to take advantage of what were then relatively new investigative techniques such as DNA profiling.

Asselin said investigators found that witnesses or tipsters are more willing to talk as time passes.

She also said that social media could be a new tool for the revamped unit.

"Someone who knew something who didn't talk, maybe sometimes sitting behind a computer is more likely to [get them to] share the information,'' she said.

The unit currently solves a few crimes a year but is hoping to dramatically increase the ratio.

"More investigators will hopefully help us arrest someone and give some answers to the families,'' Asselin said.