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PHOENIX — A 2-year-old girl accidentally head-butted an adult and suffered a bloody nose after being dropped from an 18-foot border fence in another example of the immense increase in the number of families who have come to the U.S. border with Mexico near Yuma, Arizona.

That area of the U.S. Southwest saw a 140 percent spike in the number of family units arrested by Border Patrol agents in the fiscal year that just ended in October.

The girl and two other children ages 7 and 10 were dropped from the fence by someone on the Mexico side while someone else waited on the U.S. side on Monday morning, the Border Patrol said. The families were from Guatemala and were arrested.

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Agents in the Yuma sector arrested over 14,000 families last fiscal year, compared with 6,000 the year before. Most of the families show up in urban areas of along the U.S. border with Mexico, usually waiting for agents to come find them or simply walking up to them. Many ask for asylum.

The number of families arriving at the border in that area didn't slow down even after news of family separations stunned the world.

#CBP #YumaSector camera operators observe two small children being dropped off an 18 foot wall by a suspected smuggler near San Luis, Arizona. One child received an injury to the face. #SouthwestBorder #NationalSecurity Details: https://t.co/r4tyZd9uzS pic.twitter.com/WwX1Wc5jlG — CBP Arizona (@CBPArizona) December 4, 2018

Their arrival in large numbers has shifted the job that agents normally do. Agents used to arresting drug smugglers or single men who try to cross surreptitiously now deal with families with young kids who turn themselves in. They have to make sure there are enough car seats for kids to be transported in, sort out parentage and process them with limited space.

Agents near San Luis on Monday were alerted to the family that hopped the tall fence after video surveillance spotted them east of the port of entry in an urban area with homes.

A black-and-white, grainy video shows someone on the south side of the border drop a small child over to the U.S., where another adult is waiting to catch the girl. The girl's legs dangle before she's dropped into the adult's arms.

The girl suffered a bloody nose and was treated by agents, Border Patrol spokesman Jose Garibay said.

Monday's incident happened on the day congressional leaders introduced a two-week funding bill to avert a partial shutdown of the government over President Donald Trump's border wall. Trump is pressuring Democrats to fund his border wall and has threatened other actions to deter illegal immigration as negotiations continue.