All students living in China and South Korea who took the SAT on Oct. 11 will have their test scores delayed and reviewed because of allegations of widespread cheating, officials from the College Board and its global test administration and security provider, Educational Testing Service (ETS), tell TIME.

The allegations of cheating, which are “based on specific, reliable information,” according to the officials, could be held up for as many as four weeks, potentially excluding some students for “early decision” or “early action” admissions to U.S. colleges and universities. Each individual test score will be evaluated for evidence of cheating.

“The College Board will make universities aware of the circumstances and can supply students with a letter to share with the schools to which they are applying,” ETS spokesman Thomas Ewing tells TIME. “Students should contact their preferred schools for more information.”

“Universities generally do their best to accommodate late scores from students when there are extenuating circumstances,” Ewing adds. Even if test scores are delivered in November, they will be reported as October scores, he says.

Jeremiah Quinlan, the dean of undergraduate admissions at Yale, confirms that “the administrative delay will not hurt the chance of admission for an individual applicant, since any scores that arrive before our review process is complete will be considered.” He adds that students from countries like China where there are no SAT test centers available are not required to submit SAT scores.

The College Board has faced cheating scandals in the past, although this appears to be the first time “reliable allegations” have affected more than one entire country at the same time. “We have conducted administrative reviews in a number of countries over the years including the United States when we want to assure that no student gained an unfair advantage over students who tested honestly,” Ewing says.

In May 2013, the College Board canceled a scheduled exam in South Korea because of allegations of widespread cheating, affecting an estimated 1,500 students. That was the first time allegations of cheating affected an entire country.

Students from China, India and South Korea now make up roughly 50% of the total number of international students in the U.S., according to a 2013 Institute of International Education report. The number of Chinese students studying in the U.S. has increased by 20% every year since 2008, reaching nearly 200,000 in late 2012.

Under current rules, Chinese students without foreign passports must travel outside of mainland China to take admissions tests for U.S. universities. “Chinese national students interested in taking the SAT are welcome to take it in SAT testing centers in Hong Kong, Macao or any other country such as Taiwan or Korea, among others,” the College Board website reads. Those with foreign passports can take the test in China at international schools.

“The scores under question are for Chinese test takers who tested outside of China (not Hong Kong) and NOT for those taken at the international schools in China,” Ewing says in an email.

“Based on specific, reliable information, we have placed the scores of all students who are current residents of Korea or China and sat for the October 11th international administration of the SAT on hold while we conduct an administrative review,” according to a statement from the College Board and ETS released Wednesday to TIME. “The review is being conducted to ensure that illegal actions by individuals or organizations do not prevent the majority of test-takers who have worked hard to prepare for the exam from receiving valid and accurate scores.”

The College Board sent emails this week to all students affected by this round of allegations of cheating. “Dear Test Taker: We at ETS are highly committed to quality standards and fairness,” the email reads. “After every test administration, we go to great lengths to make sure each test result we report is accurate and valid. It is with this objective in mind that we sometimes take additional quality control steps before scores are released. For the reasons stated above, your October 2014 SAT scores are delayed because they are under administrative review.”

The email ends by denouncing “organizations that seek to illegally obtain test materials for their own profit” and asks that individuals share any information with the College Board that could help in the investigation. “We take action on all credible information and go to great lengths to ensure each test result we report is accurate and valid,” the email says.

— With reporting by Tessa Berenson



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Write to Haley Sweetland Edwards at haley.edwards@time.com.