Islamist terrorists (file)
Islamist terrorists (file)Reuters

The United States said Tuesday it will boost security at government buildings, after threats from Islamist groups and following two attacks last week in Canada that killed two soldiers, AFP reports.

The "precise actions" and "precise locations" were not specified in the statement by Secretary of Homeland Security Jeh Johnson, who said they would vary, shift and "be continually reevaluated."

Johnson called it "a precautionary step, to safeguard U.S. government personnel and facilities, and the visitors to those facilities."

"The reasons for this action are self-evident," Johnson said, citing "continued public calls by terrorist organizations for attacks on the homeland and elsewhere" as well as the two attacks last week in Canada.

In the first attack, a 25-year-old who converted to Islam last year rammed his car into two soldiers in the Quebec town of Saint-Jean-sur-Richelieu and was shot dead by police. One of the soldiers later died.

The second attack occurred last Wednesday in the Canadian capital, Ottawa, as Michael Zehaf-Bibeau, also a convert to Islam, shot and killed Cpl. Nathan Cirillo at the National War Memorial in Ottawa Wednesday before attacking Parliament Hill.

Both of the attacks came as Canada deployed fighter jets to join U.S.-led air strikes on the Islamic State (ISIS) group in Iraq.

Canada is a member of the alliance Washington has forged of Western and Arab nations to combat ISIS, which seized large parts of Syria and Iraq in recent months, declaring an Islamic "caliphate" and committing widespread atrocities.

The group has called for foreign fighters to join them and promoted attacks by disaffected Muslims on Western targets.

"Given world events, prudence dictates a heightened vigilance in the protection of U.S. government installations and our personnel," Johnson said, according to AFP.