The number of conspiracy-minded antigovernment “Patriot” groups on the American radical right reached an all-time high in 2012, the fourth consecutive year of powerful growth by a movement that is becoming increasingly militant as President Obama enters his second term and Congress debates gun control measures, according to a report issued today by the SPLC.

In a letter today to U.S. Attorney General Eric Holder and Homeland Security Secretary Janet Napolitano, the SPLC warned of the potential for domestic terrorism and urged the creation of a new interagency task force to assess the adequacy of federal resources devoted to the threat.

“As in the period before the Oklahoma City bombing, we now are seeing ominous threats from those who believe that the government is poised to take their guns,” wrote SPLC President Richard Cohen, a member of the Department of Homeland Security’s Countering Violent Extremism Working Group. In October 1994, the SPLC wrote to then-Attorney General Janet Reno about the growing threat of domestic extremism; the Oklahoma City federal building was bombed six months later in the country’s deadliest act of domestic terrorism.

The SPLC found there were 1,360 Patriot groups in 2012 – an 813 percent rise since 2008, the year before Obama took office. The groups include 321 militias. These numbers far exceed the movement’s peak in the 1990s, when militias were inflamed by the 1993 Brady Bill and the 1994 assault rifle ban.

The SPLC also found that hate groups remained at a near-record level of 1,007 groups in 2012, a slight drop from the 1,018 groups documented in 2011.

The report is contained in the Spring 2013 issue of the SPLC’s quarterly investigative journal Intelligence Report. The SPLC also updated its comprehensive, state-by-state list of hate groups and interactive map showing their locations.

The resurgence of the Patriot movement, as well as the broader radical right, has been fueled by the election of America’s first black president, the troubled economy and non-white immigration. Law enforcement officials in the last several years have uncovered numerous terrorism conspiracies born in the militia subculture – plots to spread poisonous ricin powder, to attack federal installations, and to murder federal judges and other government officials.

“We are seeing a real and rising threat of domestic terrorism as the number of far-right antigovernment groups continues to grow at an astounding pace,” said Mark Potok, SPLC senior fellow and author of the report. “It is critically important that the country take this threat seriously. The potential for deadly violence is real, and clearly rising.”