BROOKLYN - Who killed "Biggie?"

That's what officials are working to figure out-- as they reopen a 13-year-old unsolved murder case.

Hip-hop artist Christopher Wallace, better known as Biggie Smalls or The Notorious B.I.G., was gunned down after a music party in Los Angeles in 1997.

The killer was never caught. But now, federal and local law enforcement agencies say they are 'actively pursuing' leads in the case.

Police say new information has surfaced -- but did not elaborate.