MOUNTAIN GATE, Calif. -

A Northern California man has pleaded guilty to two counts of first-degree murder in the slayings of two men whom authorities say he hacked to death with an ax during a 2012 rampage.

The Record Searchlight of Redding reports (http://bit.ly/1nTKNwt) that 37-year-old Thomas McDonald entered the plea on Tuesday in Shasta County Superior Court, stipulating he was insane at the time of the killing. He will be sent to a state mental hospital for a maximum sentence of 50 years to life.

Authorities say McDonald, of Mountain Gate, suspected one of his roommates was stealing from him when he went on the rampage in February 2012. He allegedly stabbed two men with a fork before randomly attacking and killing 54-year-old Karl Bradshaw and 84-year-old Ralph Torborg with a splitting maul, a long ax used to split logs.