WASHINGTON (AP) -- Hundreds of thousands of Syrians have fled that country to escape the ongoing civil war there. Migrants have trekked across Turkey, landing first in Greece, before making their way into Europe. European authorities have been overwhelmed by the mass migration. Meanwhile, the United States has announced plans to accept about 10,000 Syrian refugees trying to leave the region.
Lawmakers and more than half of U.S. governors, mostly Republicans, have raised questions about the vetting process for Syrian refugees being brought to the United States. Some said they were worried that Islamic extremists may try to take advantage of the U.S. refugee process.
Here are a few things to know:
-- The U.S. annually accepts 70,000 refugees from around the world. This group includes people fleeing violence, religious persecution and war. The Obama administration announced earlier this year that the number of people invited to move to the U.S. as refugees would be increased to 85,000 in the coming year, including about 10,000 Syrians.
-- The U.S. has helped resettle about 2,500 Syrian refugees since the war started in that country in 2011. The Obama administration said about half that group is children, while about 2.5 percent are people over the age of 60 and roughly 2 percent are single men of combat age. The overall group is almost evenly split among men and women.
-- Amid questions about background checks and security vetting, the administration for the first time this week disclosed new details about how refugees are investigated. The process is directed by the Homeland Security Department and involves the State Department and U.S. intelligence and law enforcement agencies. Refugees submit to in-person interviews overseas, where they provide biographical details about themselves, including their families, friendships, social or political activities, employment, phone numbers, email accounts and more. They also provide biometric information about themselves, including fingerprints. Syrians are subject to additional, classified controls, according to administration officials, who briefed reporters this week on condition that they not be identified by name to publicly discuss confidential details about the process. The Associated Press had been seeking details about the vetting process since September.
-- Administration officials have acknowledged that checking the accuracy or authenticity of documents provided by refugee applicants against foreign government records can be especially difficult involving countries that don't cooperate with the U.S. government, such as Syria. It can also complicate U.S. efforts to check foreign government records for local arrests or lesser bureaucratic interactions, such as bank records, business licenses or civil filings. "We do the best we can with the information we have," one U.S. official said.
-- As for concerns about potential refugees lacking documents to prove who they are, the administration officials said Syrians as a population tend to provide extensive documents involving their day-to-day lives. They often arrive with family histories, military records and other information that can be useful for American authorities investigating them.
-- Refugees who spent years waiting for approval to come to the United States said authorities asked detailed questions repeatedly in multiple interviews, including pressing them about their backgrounds and reasons for fleeing Syria. Nedal Al-Hayk, who was resettled in suburban Detroit with his family after a three-year wait, said officials interviewed him and his wife in separate rooms, asking repeatedly and in different ways where they were born, where their parents were born, what they did before and during the war or whether they were armed, part of a rebel group, supportive of the government or even politically outspoken.
-- Syrians initially file refugee claims with the United Nations High Commissioner for Refugees, which then refers them to the U.S. government. The process has no guarantee of approval and takes so long -- Syrians wait nearly three years for approval to come to the U.S. -- that experts said it would be a longshot for an extremist group to rely on the refugee program as a way to sneak someone into the United States. The Islamic State group has had far more success appealing to people already living inside the United States to commit or conspire to commit violence. Attorney General Loretta Lynch told lawmakers this week that roughly 70 people have been charged with crimes related to foreign-fighter activity and homegrown violent extremism since 2013.
-- House Republicans are proposing changes to the refugee vetting process that would include more background checks from the FBI. The proposed legislation, which could be voted on as early as Thursday, would halt refugee processing while the new protocol is established. The bill would require that the heads of the FBI, Homeland Security Department and the Office of the Director of National Intelligence certify that each refugee being admitted would not pose a threat. It could have the practical effect of keeping refugees out of the United States entirely.
The White House on Wednesday threated to veto any legislation to toughen the screening process for Syrian refugees.
Associated Press reporters Sophia Tareen in Chicago, Jeff Karoub in Detroit, and Bradley Klapper and Erica Werner in Washington contributed to this report.