George Zimmerman, charged with killing unarmed black teenager Trayvon Martin, will remain in police custody for at least one more week after a Florida court on Friday set a bail hearing date for April 20.

The 28-year-old neighbourhood watch volunteer surrendered to police on Wednesday when Florida special prosecutor Angela Corey charged him with second-degree murder in the February shooting death of 17-year-old Martin.

Zimmerman's lawyer Mark O'Mara has said he wants his client released from jail but did not request that at Zimmerman's initial court appearance on Thursday out of concern for his safety. Emotions are running high in the racially charged case, which has captured national attention.

Zimmerman is being held in protective custody for his safety in the John E. Polk Correctional Facility in the central Florida town of Sanford.

At a hastily scheduled hearing on Friday, meanwhile, the judge assigned to the case, Jessica Recksiedler, disclosed a possible conflict of interest. Her husband's law partner, Mark Nejame, is a legal analyst for television's CNN and was previously asked by Zimmerman to represent him. Nejame turned down the request.

Recksiedler did not recuse herself from the case during the hearing. She asked the attorneys to file motions if either party wants her removed from the case, and to do so before the April 20 bail hearing.

(Writing by Dan Burns; Editing by Philip Barbara)