A Florida man was sentenced to life in prison on Tuesday for attempting to provide material support to ISIS and use a weapon of mass destruction, according to the Department of Justice.

Harlem Suarez, also known as Almlak Benitez, a 23-year-old of Monroe County, Fla., was sentenced to life in prison for attempting to use a weapon of mass destruction and an explosive device.

Suarez’s Facebook postings dating back to April 2015 contained “extremist rhetoric” and promoted ISIS, federal prosecutors said.

Suarez also told an FBI informant that he wanted to make a “timer bomb.” Evidence presented during the trial showed Suarez bought components for a potential weapon of mass destruction, and planned to fill it with galvanized nails.

According to the DOJ, Suarez planned to conceal the device in a backpack and detonate it remotely with a cellular phone at a public beach in Key West.

Suarez was convicted at trial in Key West, Fla. on January 27.

In addition to the life sentence for attempting to use a weapon of mass destruction, Suarez was sentenced to an additional 20-year term for attempting to provide material support to the Islamic State.