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Capitol Police officers stand outside the Capitol in Washington, D.C., April 11, 2015. More than a dozen black and Latino girls have gone missing from D.C. this year. Some fear they could have been the victims of human trafficking. Getty Images

Officials in Washington, D.C. asked the Justice Department and the FBI to investigate the disappearances of numerous children and teenagers in the area in a letter to both departments Tuesday. More than 500 juveniles have gone missing in D.C. since the beginning of 2017: 22 cases were still unsolved as of Friday. Police, meanwhile, said there was nothing unusual about those numbers.

The letter, obtained by the Associated Press, asked FBI Director James Comey and Attorney General Jeff Sessions to “devote the resources necessary to determine whether these developments are an anomaly or whether they are indicative of an underlying trend that must be addressed.” It was signed by Congressional Black Caucus Chairman Cedric Richmond (D-La) and Del. Eleanor Holmes Norton, who represents D.C. in Congress.

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A town-hall style meeting hosted by Ward 8 councilmember Trayon White was also held Wednesday night in southeast D.C. to call attention to the situation, Fox 5 D.C. reported.

While they were concerned and actively searching for the missing children, the Metropolitan Police Department said that they were not an anomaly. Police data showed that the number of missing child cases actually dropped in the area from 2,433 in 2015 to 2,242 in 2016.

“We’ve just been posting them on social media more often,” said Metropolitan Police spokeswoman Rachel Reid, according to the AP.

The police force’s Twitter account is awash with posts asking the public for help locating missing children, most of whom are black and Latino. NBC News 4 D.C. also released an interactive map with the last known locations of the missing children.

Officials said that even if the number of missing children was less this year than in years past, an investigation should still be launched.

“We can’t focus on the numbers,” said Derrica Wilson, co-founder of the Black and Missing Foundation. “If we have one missing child, that’s too many.”

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Wilson expressed concern that the children might be victims of human trafficking, something police said they have no evidence of.

“We have no indication to believe that young girls in the District are being preyed upon by human traffickers in large numbers,” said police commander Chanel Dickerson, leader of the Youth and Family Services division, according to NBC News 4.

“It is not so much about the numbers,” said Wilson. “It is about the ones that are missing, what we can do to get them safe.”