All the little group was doing Monday was standing next to a stop sign in the Bayview district with balloons and candles to remember a friend shot over the weekend - and in a burst of gunfire, two mourners were wounded and the vigil was shattered.

It's a scene that has been repeated over and over this year.

Last week, it was a candlelight vigil in West Oakland for a young man killed a few nights before. In April, a church funeral in Oakland for another young victim was shot up, though nobody was hit.

There was once a time, experts say, when such gatherings were nearly sacred, off-limits to reprisals.

No more.

Sociologists and community leaders say memorials for the dead in tough parts of town are increasingly becoming just another target for rival gangs to intimidate their rivals. While the experts struggle to figure out why, worried mourners are thinking twice about public remembrances.

"These celebrations become provocations. It is a way of saying to the opponents, 'I dare you,' " said Frank Zimring, a professor at the Boalt Hall School of Law at UC Berkeley who studies gang violence. "It rubs the community's nose in the vulnerability and the violence."

Worried before memorial

Standing across the street from the stop sign where Monday's vigil shooting erupted, the family of Stephen Powell, 19 - the man whose killing Saturday spurred Monday's vigil - said they hadn't thought the memorial was a good idea to begin with, precisely because it might incite further violence.

"His mother told (Powell's friends) she didn't want something like that because there might be something," said Arthur Corbin, Powell's uncle.

"We don't support coming out here," said Tommie Lee Owens, another uncle. "We're going to do it properly. We don't want any violence."

Police have arrested one man, San Francisco resident Ed Perkins, 20, on suspicion of participating in the Saturday shooting during the Castro's Pink Saturday celebration that killed Powell. Police say they believe the shooting was gang related. They are seeking other suspects.

Shots not from suspect

Late Tuesday, District Attorney Kamala Harris' office issued a statement saying prosecutors decided not to file murder charges against Perkins after determining that none of the seven shots fired came from the .357-caliber revolver in his possession. Instead, Perkins will face weapons charges.

One of the two men shot at 8 p.m. Monday during the vigil at Third Street and Quesada Avenue, a 21-year-old, was hit in the cheek, police said. The other, who is 20, was shot in the leg. Investigators are not releasing the victims' names, and they have determined no motive yet for the shooting, San Francisco police Sgt. Troy Dangerfield said.

Those associated with the vigil, though, said they were fairly sure the gunfire was a continuation of the original dispute, or a reprisal of some kind.

Reasons for attacks unclear

Zimring said that while funerals have been targets for years, the spate of recent violence is striking.

"Finding the place where the enemy is having a meeting is not a new concept," he said. But "it takes a pretty twisted psychological interpretation to see a funeral as a provocation."

It is difficult to say why memorials are a target. Some believe it could be the result of escalating dares between gang members or a numbing to violence and pain brought about by drugs or a violence-ridden culture. Others think the attacks could be fueled by a simple desire to be cruel.

Whatever the motivation, it's clear that the bar has been lowered dramatically. Community leaders have been particularly shocked that churches - a regular Sunday service in Richmond also was interrupted by gunfire in February by young shooters - are now considered fair game.

"They could just be mean people who want to do further things to be mean," said Sikander Iqbal, 24, an anti-violence program manager with the Oakland community group Youth Uprising. "Even people that are involved in violence think that it's wrong."

Corbin said drugs might also play a role.

"It's hard to say what this is because these kids are on pills," he said. "People that smoke weed don't do things like this. (The shooters) are on crazy pills."

'Senseless' gunfire

Dangerfield said his department does not increase staffing or patrols when there is a vigil - but that doesn't mean police aren't concerned.

"We're always aware when there are vigils, and we try to have the officers step up," he said.

Surre Smith, 33, a lifelong resident of the Bayview who lives just a block away from the site of Monday's shooting, called the eruption of bullets "senseless." He said he is still so worried about the gunfire erupting so close to home that he is not allowing his daughter to play outside while the memorial to Powell remains at the stop sign.

"They're lighting candles for one that is dead, and they're trying to kill someone else," he said.