MILAN, N.M. (AP) — About 300 migrants who identify as transgender were booked into the custody of U.S. immigration authorities since Oct. 1, marking the highest number since officials began keeping track in 2015.

U.S. Immigration and Customs Enforcement is considering opening a second permanent facility where transgender migrants can be detained amid the influx of Central Americans crossing the U.S.-Mexico border.

The agency’s Enforcement and Removal Operations field office director Corey Price says all options are being reviewed.

Price on Wednesday led the first media tour of the agency’s only permanent transgender detention unit. The rural New Mexico unit opened in 2017.

He acknowledged a second unit would be a significant investment given the higher costs associated with transgender detainees.

The agency was criticized for the deaths of two transgender women.