BOISE, Idaho — A Nampa man admitted last week to a terrorism charge as part of an agreement with prosecutors that allowed him to shed other counts.

Grant Stevenson pleaded guilty to felony terrorism after sending online messages to Nampa Police threatening to release a deadly nerve agent at a Nampa apartment complex and set off bombs around town in March. 

RELATED: 'Death to America': Terrorism suspect threatened sarin gas attack, car bombings in Nampa, police say

Detectives quickly connected the threat to Stevenson, who had a history of calling in false bomb threats. He was arrested, and has been held in the Canyon County Jail on a $2 million bond since. 

Authorities say Stevenson did not actually have access to sarin gas or explosives. 

RELATED: DHS announces plan to combat domestic terrorism

Prosecutors moved to drop a felony charge of threatening to use weapons of mass destruction and two misdemeanor counts of telephone harassment as part of the plea deal. 

Stevenson's lawyer said last month both sides have agreed on a 15-year prison sentence, with three years before Stevenson will be allowed to seek parole. If he had been convicted of the terrorism charge at trial, he could have faced a life sentence. 

In addition, prosecutors will ask for up to $125,000 in restitution. 

Sentencing in the case is set for Dec. 2. 

RELATED: Plea agreement reached in Nampa terrorism case

Watch more Crime:

See them all in our YouTube Playlist: