Labor Day weekend brought gun violence to Charlotte, North Carolina -- at a frequency level the area's police chief could not recall previously witnessing. The latest attack Saturday led to the death of a 7-year-old boy at a birthday party. Three others were injured.

Officers are still searching for the alleged gunman. They were called to the scene at around 9 p.m. Saturday, NBC News reported. Medics helped treat three others -- two adults and one child -- who had been shot and faced nonlife-threatening injuries. The boy, identified as Kevin Rodas, was taken to a hospital, where he died.

The Charlotte-Mecklenburg police department is still investigating and has called in help from other special units, including the K-9 and gang units, the Charlotte Observer reported. There were reports of a gunman armed with a high-powered rifle walking the streets near the crime scene. Police walked the streets “shoulder-to-shoulder,” Deputy Chief Jeff Estes told a press conference Sunday, as recorded by WSOC-TV, Charlotte.

Officials have also requested officers who were previously on vacation come into the office to assist in the investigation and patrol the city, Estes said. “It’s a sad state of affairs in the city, in our country where a 7-year-old boy can’t be free to celebrate a birthday party without being murdered,” he said. “We are calling in officers from their days off. We’ll have additional officers in every single patrol.”

Saturday’s shooting is the latest in a series of violent crimes. There have been four shooting incidents so far during this Labor Day weekend, the Associated Press reported. Ten people have been shot, five of them fatally, Estes confirmed. The department did not have an update on the motives or suspects in those crimes.

When asked if the level of crime and possession of firearms was an imminent threat to the public, Estes said: “Oh, absolutely. Illegal firearms and they’re high-capacity. That’s what we’ll do this weekend. We’ll specifically target illegal firearms and street-level violence.”