A social worker who was detained in Mexico while delivering Christmas gifts to children at an immigration camp along the southern border was released on Christmas Eve.

On Monday, Anamichelle Castellano, along with a woman volunteer, were gifting presents to youth from Brownsville, Texas into Matamoros, Mexico on behalf of her nonprofit organization the Socorro Foundation.

According to Castellano’s family, Mexican authorities discovered a small box of ammunition inside the car she was driving. Her relatives say the box was left by Castellano’s husband, who recently returned from a hunting trip. However, Mexico has strict laws against entering the country with guns or ammunition.

According to the Guardian, the woman and her 9-year-old daughter spent the night at a government office on Monday and awoke to give a statement to a prosecutor on Tuesday before they were allowed to return to the U.S.

The woman’s car, along with the 300 gifts she was delivering, are still in Mexico.

The gifts were for children seeking asylum in the U.S. who have been forced to await their hearings in camps along the border due to President Donald Trump’s controversial Remain in Mexico policy.

The woman, who had to pay a fee of $4,000 and was issued a court date to meet with a judge in Reynosa, Mexico, said she will comply with authorities in order for her to continue to do her service work.

“I serve refugees,” she said, according to the newspaper. “To tell me that I can’t go back and give them their gifts and their needed supplies, I can’t risk that.”