US officials have confirmed that over a six-week period, 1995 children were separated from their parents or legal guardians under its new 'zero tolerance' immigration policy.
That number equates to 46 children a day.
The Trump administration announced the policy in April. Any adults who have been referred to Homeland Security for illegal entry into the US now have their children take from them.
Homeland Security has denied reports they took a breastfeeding child from a parent.
"We do not separate breastfeeding children from their parents. That does not exist, that's not a policy, that's not something that DHS does," a DHS official told NBC News.
Comparatively rare under the Obama administration, over seven months prior to February 1800 immigrant families were separated - but mainly for medical and security reasons, Reuters reported.
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The new zero tolerance policy has been heavily criticised by Democrats and Republicans alike, but Attorney General Jeff Sessions has defended it.
"If you cross the southwest border unlawfully, then the Department of Homeland Security will arrest you and the Department of Justice will prosecute you. That is what the law calls for and that is what we are going to do," Sessions told NBC News.
Officials could not confirm if children were able to say goodbye to their parents and guardians before being taken away.