A U.S. man has been charged with using a website to “promote violent jihad” and posting instructions on how to make a bomb.

The U.S. Justice Department said Thursday 22-year-old Emerson Begolly moderates the popular Ansar al-Mujahideen English Forum. In a statement, officials accused Begolly of placing a number of postings in the last year, encouraging attacks against U.S. targets including police stations, post offices, and synagogues.

The statement says Begolly also posted comments praising the October 2010 shootings at the Pentagon and the Marine Corps Museum, saying he hoped the shooter had been inspired by his postings encouraging violent acts that “seem small but cause big damage.”

Assistant Attorney General Lisa Monaco said the case shows how “homegrown extremists” can use the Internet to incite violence.

U.S. Attorney Neil MacBride said the allegations show how U.S. youths can be influenced by and participate in jihadist propaganda that poses “a serious threat” to public safety.

Begolly has been charged with solicitation to commit a crime of violence and distribution of information relating to explosives. If convicted, Begolly could face up to 30 years in prison.

The Justice Department says Begolly also faces separate charges from February, related to firearms and for allegedly assaulting federal agents. Those charges carry a maximum penalty of life in prison.