JOHANNESBURG (Reuters) - A South African judge on Tuesday ordered four men accused of murdering reggae star Lucky Dube held without bail after they made a brief appearance in a court packed with the singer's fans.

The murder of Dube, South Africa's biggest-selling reggae singer, stunned a nation already traumatized by one of the world's worst violent crime levels and prompted widespread calls for a dramatic police crackdown on criminals.

The suspects, identified by SAPA news agency as Sifiso Mlanga, Julius Gxowa, Thabo Mafoping and Mbofi Mabe, were heckled as they were led back into the holding cells at the magistrate's court in Johannesburg.

They are charged with murder, attempted hijacking and possession of an unlicensed firearm and ammunition in connection with the October 18 slaying of Dube, who was shot in front of his kids in a Johannesburg suburb in an apparent botched carjacking.

The men, two of whom are Mozambicans, will appear in the same court on October 30 to have their applications for legal aid processed, SAPA reported.

South Africa's murder rate jumped 2.4 percent between April 1, 2006, and March 31, 2007, with 19,202 murders recorded in the period. The number of rapes, carjackings and assaults also remained alarmingly high in the period.

Dube, who recorded more than 20 albums in his career and won over 20 awards locally and internationally, will be buried on Sunday in Newcastle, South Africa. His funeral is expected to draw large numbers of fans as well as members of the public.