WASHINGTON -- A Senate appropriations panel voted Tuesday to give the Obama administration $2 billion it requested to handle the dramatic increase in child immigrants caught trying to illegally cross the Mexican border without their parents.

The money is more than $1.1 billion more than President Barack Obama initially asked for in his budget proposal for the Health and Human Services division that cares for and houses immigrant children caught alone at the border. It would effectively come from yet unspecified changes in mandatory programs.

The number of children found trying to cross the Mexican border without parents has skyrocketed. Between 2008 and 2011, the number of children landing in the custody of HHS's Refugee Resettlement fluctuated between 6,000 and 7,500 per year. In 2012 border agents apprehended 13,625 unaccompanied children and that number surged -- to more than 24,000 -- last year. The total is expected to be as high as 90,000 this year.

Office of Management and Budget Deputy Director Brian Deese wrote to committee chairwoman Sen. Barbara Mikulski, D-Md., to formally ask for more money on May 30.

The HHS budget approved by the committee would also allow the government to move money from other areas if the flow of child immigrants grows beyond the latest estimate of up to 90,000.

The full Senate will have the final say on its version of the HHS budget. And the House has not yet acted on the issue.