Rapper Drake caused chaos by making a surprise appearance at a university gig on Friday (19Oct12) as excited fans scrambled to get closer to the stage.

Headliner 2 Chainz was performing his track No Lie when he brought collaborator Drake out as a special guest during Howard University's International YardFest concert in Washington, D.C.

Pandemonium ensued as the crowd pushed forward, resulting in photographers and concert-goers being shoved into barricades and leaving several students with minor injuries.

The hip-hop stars then halted their set to ask the audience to step back as guards helped crushed fans over the barriers and to safety.

Other artists who performed at the annual YardFest show included T.I., Pusha T and Meek Mill.