WASHINGTON, D.C. (NBC) — A fourth bus carrying migrants from the Texas-Mexico border arrived in Washington, D.C. Saturday.

The group was dropped off at Union Station and met by representatives from the Central American Resource Center.

The busing strategy is part of Texas Governor Gregg Abbott’s response to President Biden ending Title 42 expulsions in May.

The governor said migrants are being sent to the nation’s capital where “the Biden administration can more immediately address the needs of the people they are allowing to cross the border.”

Migrants must volunteer to be transported as well as show documentation from the Department of Homeland Security.

Texas Division of Emergency Management Director Nim Kidd said they will use as many buses as they need to follow the governor’s directive.