The Southern Baptist Convention, the largest U.S. Protestant denomination, said on Friday that several of its entities were being investigated by the Justice Department, after a report found the church had mishandled sex abuse claims and mistreated victims.

The Convention did not provide details on the inquiry and the Justice Department did not immediately respond to a request for comment. But the church's executive committee said in a statement it would fully cooperate with the probe and would "transparently address the scourge of sexual abuse."

An internal report commissioned by the Convention and released in May found that complaints of sex abuse by pastors and staff were either ignored or covered up by top clergy, a practice that occurred over decades.

The Convention, which has 13.7 million members, has since issued a formal apology over the abuse and released a list of hundreds of offenders who have been criminally convicted, had civil judgments against them or confessed their actions. 

In its statement, the Convention's executive committee said the Justice Department inquiry "will include multiple SBC entities." Each entity is resolved to fully and completely cooperate, it added. 

"Leaders across the SBC have demonstrated a firm conviction to address those issues of the past and are implementing measures to ensure they are never repeated in the future," it said.