The U.S. refugee program came under fresh criticism Friday after federal authorities revealed that two Iraqi-born men arrested on terrorism-related charges had come to America as refugees.

While there was no evidence the men intended or planned attacks in the United States, Republican lawmakers already concerned about the federal government's ability to properly vet Syrian refugees said the cases highlight weaknesses in the program that put Americans' safety at risk.

"How many ticking time bombs are we going to bring in in this refugee program without a proper vetting system in place?" Rep. Michael McCaul, R-Texas and chairman of House Homeland Security Committee, said at a news conference.

He and other GOP lawmakers urged the Senate to pass legislation to block refugees from Iraq and Syria until screening is improved. The House passed a bill in November.

The uproar comes after weeks of fervent debate in Washington and on the presidential campaign trail about tighter security screens in the wake of attacks in Paris and San Bernardino, California.

Immigrant advocates said they have full confidence in the vetting process and that tens of thousands of Iraqi refugees have been successfully resettled under the program.

On Thursday, federal authorities in California accused 23-year-old Aws Mohammed Younis Al-Jayab of Sacramento of traveling to Syria to fight and lying to U.S. officials about it. Al-Jayab had come to the United States as a refugee in October 2012, and discussed on social media how he fought against the regime in Syria as a teen, authorities said.

In Texas, 24-year-old Omar Faraj Saeed Al Hardan of Houston was indicted on charges that he tried to provide material support to the extremists. Both suspects are Palestinians born in Iraq, authorities said.

The U.S. annually accepts 70,000 refugees from around the world, including people fleeing violence, religious persecution and war, and has announced plans to increase the number to 85,000 this year.

Since the 2001 terrorist attacks, about 785,000 refugees have arrived in the country, and fewer than 20 have been arrested or removed over terrorism-related concerns, according to the State Department.

White House spokesman Josh Earnest said Friday the screening of refugees is rigorous and thorough. He repeated the administration's opposition to proposals that would impose a religious test or bar individuals from the U.S. based on their ethnicity.

"That doesn't represent who we are as a country and, most importantly, it's not going to keep us safe," Earnest said.

More than 127,000 Iraqi refugees have arrived in the United States since October 2006, with the largest numbers headed toward California, Michigan and Texas, according to State Department statistics. Some Iraqis go through the U.N. refugee agency, while some can apply directly to the refugee program in Jordan, Egypt and Iraq.

Melanie Nezer, vice president for policy and advocacy at the Jewish refugee agency HIAS, said she worries the recent backlash might place law-abiding refugees under suspicion. She said she has confidence in the government's screening measures and that these are continually updated by federal intelligence officials.

"The vast majority of refugees, including Iraqi refugees, have not caused any harm to our country and will not cause any harm to our country," she said.

Federal authorities said Al-Jayab promised to provide weapons training to Al Hardan and advised him on how he would be assigned to the battlefield once he arrived in Syria. While authorities say Al Jayab fought twice in Syria, including with a group eventually linked to Islamic State, there is no indication that Al Hardan actually traveled there.

Al Hardan became a legal permanent resident of the United States in 2011 and applied in 2014 to become a U.S. citizen, authorities said. Al-Jayab was interviewed by immigration officials in 2014 for his green card and did not disclose his recent travel to Syria, authorities said.

Security screenings for immigrants and travelers have come under increased scrutiny because of recent attacks. Rules have been tightened for visa-free travel to the United States and lawmakers have vowed to look into the fiancé visa program, which was used by the husband-and-wife attackers in San Bernardino who killed 14 people last month.

On Friday, senior White House officials and members of the president's national security team traveled to Silicon Valley to seek tech industry help to stop the Islamic State and other groups from radicalizing people online.


Associated Press writers Matthew Daly in Washington and Don Thompson in Sacramento, California, contributed to this report.