Two men from the Middle East 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, the U.S. officials said on Thursday.
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 U.S. Department of Justice said Aws Mohammed Younis Al-Jayab, 23, came to the United States in 2012 as a refugee from Syria.
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Texas Lieutenant Governor Dan Patrick, a Tea Party Republican, cited the arrest in Houston as a reason why Texas has been seeking to block Syrian refugees from resettling there.
"This is exactly what we have repeatedly told the Obama administration could happen and why we do not want refugees coming to Texas. There are serious questions about who these people really are, as evidenced by today's events," Patrick said in a statement.
Republican leaders have been calling on President Barack Obama, a Democrat, to move with caution in allowing refugees from Syria to resettle in the United States.
Al-Hardan was charged with providing material support to the Islamic State militant group and for making false statements about ties to the group when seeking U.S. naturalization, according to an indictment in federal court in Houston unsealed on Thursday.
In California, Al-Jayab was arrested on Thursday on a federal charge of making a false statement involving international terrorism, the U.S. Department of Justice said.
The U.S. attorney for Sacramento, Benjamin Wagner, said in a statement there were no indications Al-Jayab had planned any attacks in the United States.
"While he represented a potential safety threat, there is no indication that he planned any acts of terrorism in this country," Wagner said.
Wagner's spokeswoman, said Lauren Horwood, said: "There is no current threat to public safety associated with this arrest."
In a criminal complaint, the Federal Bureau of Investigation said Al-Jayab lied about traveling back to Syria and about posting on social media his support for what the government said were terrorist groups.
"O God, grant us martyrdom for your sake while engaged in fighting and not retreating; a martyrdom that would make you satisfied with us," the FBI said Al-Jayab wrote to someone identified only as "Individual I," who resides in Texas.
The Justice Department said that the year after Al-Jayab came to the United States, 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 Friday, Horwood said.