Washington (CNN) Hundreds of children separated from their parents at the US-Mexico border remain separated from them, including 497 in government custody, according to a new court filing Thursday.

The figure includes 22 children under the age of 5 still in government care. Six of those are 4 years old or younger whose parents were deported without them.

A total of 1,937 children have been reunified with parents, up only 14 from last week.

The court filing from the Justice Department and the American Civil Liberties Union case describes a slow and laborious process to try to connect the families that have been separated.

It remains unclear exactly how many parents were deported without their children, though it's in the hundreds. By the government's latest count, there are 322 deported parents who have children still in custody.

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