Times coverage: 49th Street Massacre

The role race and ethnicity play in street violence has long been debated. In 2006, concern was particularly high about racial tensions in Los Angeles, with deadly race riots in county jails and brawls on local high school campuses between black and Latino students.

Amid worries and rumor that such tensions would spill into neighborhoods, David Marcial, 10, his uncle Larry Marcial, 22, and Luis Cervantes, 17, a neighbor of the Marcial family -- all Latinos -- were killed by gunmen identified by witnesses as black. Times reporter Jack Leonard has the story what prosecutors ultimately argued was the motivation for the daytime attack on a South Los Angeles street:

On a summer afternoon nearly four years ago, two men carrying AK-47 assault rifles climbed out of a dark red sedan on a quiet South Los Angeles street and opened fire. One gunman shot a 10-year-old boy riding a bicycle, then stood over the child and continued firing at point-blank range. Three people, including the boy, were killed.

The assailants were described as black, the victims were Latino. Police said that the dead were not connected to gangs but that they suspected the attackers were.

What became known as the 49th Street Massacre was one of several high-profile interracial gang crimes that stoked fears among some minority activists of a possible race war.

But as the murder trial of two alleged gang members accused in the killings draws to a close, little evidence has pointed to race as a principal motive in the shooting.

Prosecutors contend that Ryan T. Moore, 36, and Charles Ray Smith, 41, mistook the victims for rival gang members in a tit-for-tat feud over turf, drugs and pride. Defense attorneys do not dispute the prosecution's theory but say authorities identified the wrong men as the killers.

Although examples of interracial gang killings have heightened racial tension in recent years, the case helps illustrate how complex a role race plays in L.A.'s gang violence. Experts say most conflicts involve gangs of the same ethnicity. But whether hostilities cross racial lines or not, innocent people are frequently caught in the violence.

Keep reading: L.A.'s 49th Street massacre may not have been about race