The pace of Syrian refugees entering the U.S. has surged in recent weeks, government figures show, putting the Obama administration on track to meet its target of admitting 10,000 Syrian refugees before the end of September -– and reviving Republican concerns about the security implications.

State Department reports show that 2,340 Syrian refugees arrived last month in the United States.

That's more than what occurred during the entire seven months after President Obama directed his team to prepare for 10,000 admissions from the war-torn country. Total admissions for the current budget year, which ends Sept. 30, now come to about 7,900, and the vast majority of them are Sunni Muslims, records show.

Homeland Security Secretary Jeh Johnson said earlier this week the U.S. is on track to meet the 10,000-refugee goal.

If the pace from June and July continues this month, the target should be reached with a couple of weeks to spare, before Obama heads to the United Nations to urge world leaders to admit more refugees and increase funding for relief organizations.

But amid new predictions from FBI Director James Comey of a “terrorist diaspora out of Syria,” some Republicans are ramping up warnings that the flow of refugees poses a threat to America and Western Europe.

Rep. Vern Buchanan, R-Fla., urged President Obama in a letter Thursday to “immediately stop accepting Syrian refugees as a matter of national security.”

He wrote: “We are seeing a clear pattern in which a number of recent attacks have been carried out by ISIS terrorists with ties to Syria, including: the July 24 bombing of a music festival in Germany; the July 26 killing of a French priest; and the July 24 murder of a German woman with a machete. Syrian refugees played a part, either as attackers or accomplices, in all three attacks.

“In the context of this clear threat, your goal of admitting 10,000 Syrians as a part of a so-called ‘surge operation’ is extremely troubling. … Terrorists are leaving Syria disguised as refugees and carrying out attacks in the West. The prudent course of action is to halt all admissions of Syrians into the U.S. until the safety of Americans can be guaranteed,” he wrote.

In a statement Thursday night, the Donald Trump campaign said the administration was “dangerously expediting their admission.”

According to federal government data, the Syrian refugees are being re-settled in states across the country, including Arizona, California and New York.

The White House, though, has emphasized that the screening process for refugees takes 12 months to 18 months and includes in-person interviews and a review of biographical and biometric information. The administration also has said it is focused on bringing in refugees who are in the most desperate situations, such as families with children and those in need of medical care. In the year prior to Obama's new target, the U.S. accepted about 1,680 Syrian refugees.

Secretary of State John Kerry, speaking with reporters during a visit to Buenos Aires, Argentina, said the United States has developed "sufficient methods" of screening would-be refugees.

"We are very comfortable that we are bringing people in who will be a great plus to our country," Kerry said.

Kerry said that "not one event in the United States, of terror" has been committed by a refugee allowed to re-settle in the U.S.

But two Iraqi refugees were arrested in 2011 for plotting to send weapons and money to Al Qaeda operatives fighting against U.S. troops back in Iraq. The scheme was foiled, but the case did leave jitters about whether extremists could slip in among the Syrian refugees.

"We believe ... the people who are fleeing Syria are the most harmed by terrorism. They are parents. They are children. They are orphans," Kerry said. "It is very important that we do not close our hearts to the victims of such violence."

Kerry also applauded Argentina's pledge to re-settle 3,000 Syrian refugees in the South American country and said the United States is committed to working with the government there on security issues.

The Associated Press contributed to this report.