A Mother's Day parade in New Orleans was ruined on Sunday when at least one gunman opened fire on the crowd, wounding at least 18 (UPDATE: 19) people, including two children: a boy and a girl, both 10 years old. 

So far, it looks like most of the casualties from the mass shooting are in good condition. Here's New Orleans PD spokesperson Remi Braden explaining what they know to the Times-Picayune

Many of the victims were grazed, some by bullets that ricocheted," Braden said in an email. "At this point, there are no fatalities, and most of the wounds are not life-threatening. "But all medical conditions are not known at this time as victims were rushed to nearby hospitals," Braden continued. "Detectives are conducting interviews, retrieving any surveillance video in the area and, of course, collecting all evidence. This is an extremely unusual occurrence, and we're confident that we will make swift arrests." 

Both children, as the Associated Press notes, were grazed in the shooting. They're in good condition. At the time of the shooting, about 200 people were in the immediate vicinity, out of the crowd of about 400 participating in the parade. Police are looking for three suspects seen running away from the scene. No arrests have been made. 

The Mother's Day celebration was a "second-line" parade, a tradition specific to New Orleans. It's kind of a mix between a block party and a more traditional walk-down-the-street parade: a brass band leads an informal procession of dancers and revelers through the streets. They happen pretty much every weekend in New Orleans this time of the year, as the Times-Picayune notes. The century-old tradition is associated with, but not exclusive to, the city's African American community. They're usually organized by neighborhood groups, in this case, the Original Big 7 Social Aid and Pleasure Club, who have hosted the Mother's Day second line in the 7th Ward since 2001.  

While not commonplace, violence at second lines is not unheard of (there was even a second-line shooting in an episode of "Treme," for instance), and it's been a source of tension in the past between city law enforcement and parade organizers. Just after Hurricane Katrina devastated the city, New Orleans raised the fees on "second line" permits dramatically in order to, as they argue, pay for the increased costs of policing them due to increased violence at the parades. That action prompted a huge response from second-line supporters, who argued that the fee increase unfairly targeted the predominantly African-American communities in the city who put on the parades.