OTTAWA -- Ottawa serial killer Camille Cleroux, who killed two ex-wives and a neighbour over a 20-year period, has died in a British Columbia prison.

Correction Service Canada says Cleroux died of apparent natural causes at the Pacific Institution in Abbotsford, B.C. on Jan. 17.  At the time of his death, Cleroux was serving a life sentence for first-degree murder and two counts of second-degree murder.

In June 2012, Cleroux admitted to killing ex-wives Lisa Roy and Jean Rock and neighbour Paula Leclair. Roy disappeared in 1990, while Rock went missing in 2013.

In 2010, Cleroux was charged in the death of Leclair, a former neighbour. The 64-year-old's body was found in a wooded area near her home in June 2010.

A judge sentenced Cleroux to life in prison with no chance of parole.