Republican presidential hopeful Ted Cruz cited the arrest in Houston and Sacramento of two men from the Middle East as a reason to block Syrian refugees from resettling in the US. Two men who came to the United States as refugees more than three years ago were arrested on federal charges in California and Texas involving international terrorism related to Islamic State (Isis), the US officials said on 7 January.

"Isis has declared war on America. They intend to wage jihad, the attack in Paris, the attack in San Bernardino, Isis intends to carry as many of these attacks out as possible. And these arrests tonight underscore how utterly indefensible President Obama and Hillary Clinton's proposal is to bring tens of thousands of Syrian refugees into this country," Cruz said to reporters.

Republican leaders have been calling on President Barack Obama to move with caution in allowing refugees from Syria to resettle in the United States. President Obama has directed his administration to prepare to take in at least 10,000 Syrian refugees over the year during 2016, the White House said in September 2015.

It was the first specific commitment the US has made toward increasing its acceptance of refugees from the war-torn country. Since the start of the Syrian civil war in 2011, the US has taken in over 1,500 refugees.

The men, arrested in Sacramento and Houston, were not involved in a single plot, but they may have been in contact with each other, a source familiar with the two cases said. Both men are Palestinians who were born in Iraq. The man arrested in Houston, Omar Faraj Saeed Al-Hardan, entered the United States as a refugee in November 2009, according to a court document. In Sacramento, the US Department of Justice said Aws Mohammed Younis Al-Jayab, 23, came to America in 2012 as a refugee from Syria.

Al-Hardan was charged with providing material support to the IS militant group and for making false statements about ties to the group when seeking US naturalisation, according to an indictment in federal court in Houston unsealed on 7 January. In California, Al-Jayab was arrested on 7 January on a federal charge of making a false statement involving international terrorism, the US Department of Justice said. The US attorney for Sacramento, Benjamin Wagner, said in a statement there were no indications Al-Jayab had planned any attacks in the US.

In a criminal complaint, the Federal Bureau of Investigation (FBI) said Al-Jayab lied about travelling back to Syria and about posting on social media his support for what the government said were terrorist groups. The Justice Department said that the year after Al-Jayab came to the US, he went overseas, later telling officials that he had gone to Turkey to visit family.

The complaint includes numerous social media postings and other communications in which Al-Jayab discussed jihad, using assault rifles and training with militants. He also said he was in Syria. Al-Jayab is scheduled to appear in federal court in Sacramento on 8 January, Wagner's spokeswoman, said Lauren Horwood, said.