Chris Brown is “totally paranoid” after receiving a mirage of death threats following his – ahem – “alleged” beating of former girlfriend Rihanna earlier this year.

The 20-year-old singer – who has pleaded not guilty to assaulting the “Umbrella” singer in an altercation las February – has employed increased security amid concerns he could be attacked at any moment, The Chicago Sun-Times has learned.

“It seems the music star has been targeted with death threats the authorities believe are actually legit…Brown is said to be ‘totally paranoid’ about the threats on his life and has become obsessed with his security.”

A Los Angeles Police Department source claims these disguised guards have at times been women, but that they are “easily as tough as men.” The LAPD spy also reveals that the department is investigating claims thaat the threats on Chris’ life could be from an organization called the Women’s Protection Action League.

In other Chris & Rihanna news, the 21-year-old songstress was served with a subpoena to attend a Superior Court hearing in Chris’ case on June 22.

“By prearrangement with the District Attorney, Rihanna was served Tuesday June 9, 2009, at my office with a subpoena to appear at the preliminary hearing, scheduled for June 22, 2009,” Rihanna’s attorney told ET on Wednesday. “If that hearing does go forward, Rihanna will appear, and will answer all questions posed to her by the District Attorney and Mark Geragos, Chris Brown’s lawyer.”