Republican U.S. Presidential nominee Donald Trump attends a campaign event at the Greater Columbus Convention Center in Columbus, Ohio August 1, 2016. REUTERS/Eric Thayer

WASHINGTON (Reuters) - U.S. Republican presidential candidate Donald Trump on Monday fired senior adviser Ed Brookover, two sources close to his campaign said.

The sources did not say why Brookover was fired.

A statement from the Trump campaign confirmed Brookover had left.

“The campaign has parted ways with Ed, but we are thankful to him for his many contributions and appreciate his continued support,” the Trump campaign said in a statement.

Brookover did not immediately respond to a request for comment.

Brookover, who joined the Trump campaign in March, was appointed in June to serve as a liaison between the Trump campaign and the Republican National Committee.

Prior to joining Trump, Brookover served as campaign manager to Ben Carson during his failed bid for the Republican nomination.