DENVER -- A Denver man convicted of pushing his wife to her death from a cliff in Rocky Mountain National Park has been sentenced to life in prison, with no chance of parole, CBS Denver reported.

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U.S. District Judge R. Brooke Jackson on Tuesday imposed the mandatory sentence against 59-year-old Harold Henthorn, who was convicted of murder.

Henthorn's second wife, Toni Henthorn, plummeted 130 feet in a remote, rocky area of the park in September 2012. Harold Henthorn says he took her there to celebrate their 12th wedding anniversary.

Prosecutors say he wanted to collect $4.7 million in life insurance policies she didn't know existed.

Authorities continue to investigate the death of Henthorn's first wife, who was crushed when a car slipped off a jack while they were changing a flat tire in 1995. Harold Henthorn hasn't been charged in that death.