The probe by the U.N. Population Fund (UNFPA) comes after Ugandan media reported this week that armed groups had been forcefully conducting FGM in Kween district near the eastern border with Kenya.

The reports sparked alarm across the east African nation, which has a strict anti-FGM law in place that has helped reduce the number of FGM cases in recent years.

“We have dispatched a fact-finding mission to Kween which will hopefully provide us with more background on this unexpected surge,” Alain Sibenaler, UNFPA country director in Uganda told the Thomson Reuters Foundation by email.

“But what we know for sure is that FGM is being eliminated and therefore the recent incidents do not erase the achievements of the campaign,” he said, referring to joint efforts since 2009 by authorities, charities and the U.N. to curb the practice.

About 200 million girls and women worldwide have undergone FGM, which usually involves the partial or total removal of the external genitalia, according to U.N. estimates.

Seen as necessary for social acceptance and increasing a woman’s marriage prospects, FGM is prevalent across parts of Africa, Asia and the Middle East.

Performed by traditional cutters, often with unsterilized blades, girls can bleed to death or die from infections. FGM can also cause lifelong painful conditions such as fistula and fatal childbirth complications.

At least 100 girls and women in Kween were forced to undergo circumcision by groups led by elderly women and accompanied by men with machetes, Ugandan media reported.

The news reports triggered debate in the country’s parliament and the government ministers vowed to take action against the “inhuman” practice.

Uganda criminalized FGM in 2010 with a maximum penalty of 10 years imprisonment. Compared to other African nations, prevalence rates are low with only 0.3 percent of women aged between 15 and 49 having been cut, according to government data.

However, in some communities in the east and northeastern parts of the country, prevalence rates are more than 90 percent, the U.N. said.

Campaigners said more public awareness campaigns are needed, and law enforcement should be stepped up in remote and rural areas where the tradition persists.

“The eastern part of Uganda had experienced long periods of violence and insecurity that made it difficult to enforce the law as effectively as it had ought to be,” said Jean-Paul Murunga of campaign group Equality Now in Nairobi, Kenya.

“This is an opportunity for the government to take advantage of the current tranquility to reach the remotest areas and enforce the anti-FGM law to the fullest.”