Secret Service Investigating Kal Penn Robbery

4/21/2010 8:30 AM PDT
The scumbag who robbed Kal Penn at gunpoint in D.C. yesterday picked the wrong guy to mess with -- law enforcement sources tell TMZ the Secret Service is now on the case.

Turns out, the bad guy didn't just take Penn's wallet, the perp also made off with Kal's two cell phones -- one of which belongs to the U.S. government. 

Penn is currently a member of President Barack Obama's staff -- serving as the Associate Director in the Office of Public Engagement -- and since the crook took Kal's government issued cell, the Secret Service is now joining with the D.C. Metro Police Department to hunt for the bad guy.

Sources tell us Penn contacted White House communications, who stopped service on the stolen phone ASAP and issued him a new cell. We're told "no information was compromised because no official numbers were in the phone."