U.S. federal prosecutors say a suspect is in custody in connection with a series of church burnings in the southern state of Louisiana.

The fires took place at three historically African American churches in St. Landry Parish between March 26 and April 4. The churches were not occupied at the time of the fires, and no one was injured.

A statement from U.S. Attorney David Joseph did not identify the suspect, but said the person is in state custody.

“The U.S. Attorney’s Office, ATF (Bureau of Alcohol, Tobacco, Firearms and Explosives), and FBI are working with state and local law enforcement and stand shoulder-to-shoulder with the victims and those St. Landry Parish residents affected by these despicable acts,” Joseph said.

The Louisiana Office of State Fire Marshal has said investigators “identified suspicious elements” with the fires at St. Mary Baptist Church, Greater Union Baptist Church and which damaged Mount Pleasant Baptist Church.

Authorities planned to release more information about the case at a Thursday news conference.