*The third-annual Roots Picnic, featuring headliner Vampire Weekend, is set for June 5 at Philadelphia’s Penn’s Landing pier.

Drummer ?uestlove hinted in a Twitter video that the surviving members of Run D.M.C. would be reuniting for the show.

“If you were at the festival last year, you will notice that The Roots lived out their fantasy of doing the classic ‘It Takes a Nation of Millions’ album with Public Enemy,” Questlove said. “Are we going to top that? We are absolutely going to top that. This is a reunion we thought we would never get. We’ve been waiting to make this reunion happen for the longest, it’s so incredible, I don’t even want to tell you who it is.”

Going on to drop a major hint, Questlove said, “This is all I’m gonna say,” as he put on a thick gold chain and black hat before striking a distinctive Run-D.M.C. pose. “This should say it all. This is one show you don’t want to miss.”

A series of tweets also hinted that Amy Winehouse would be participating in the Roots Picnic and in the surprise reunion in some form.

What has been confirmed is a line-up featuring Clipse, Mayer Hawthorne, Nneka, The Very Best, Tuneyards, Das Racist, Bajah and the Dry Eye Crew, and Pattern Is Movement. Questlove, whose real name is Ahmir Thompson, also will play a set with DJ Jazzy Jeff; and Tariq “Black Thought” Trotter will perform with his side project the Money Making Jam Boys.

Tickets for the Roots Picnic go on sale Friday (3/5) morning at LiveNation.com.