Two people have been killed and 28 wounded in a mass shooting in Baltimore, including three who are in critical condition, police have said. The Baltimore police department’s acting commissioner, Richard Worley, confirmed there were a total of 30 victims during a press conference at the scene on Sunday afternoon. He said “more than one shooter” was involved, and that no arrests have been made. The shooting took place shortly after 12.30am at a block party in the Brooklyn Homes area of south Baltimore. An 18-year-old woman was pronounced dead at the scene, and a 20-year-old man died later in hospital. Hundreds of people were gathered in the area for an event called “Brooklyn Day”, a witness told local television station Fox 45. That witness described hearing 20 to 30 shots fired. The ages of the victims ranged from 13 to 32, Worley said. Nine were taken by ambulance and 20 others walked into area hospitals with injuries from the shooting. “This was a reckless, cowardly act of violence that has taken two lives and altered many, many more. We will find those who are responsible and we will not stop until we do so,” Baltimore’s mayor, Brandon Scott, said on Sunday afternoon. “It’s another glaring, unfortunate example of the deep issues of violence in Baltimore, in Maryland and in this country, particularly gun violence and the access to illegal guns. “We need accountability at every level, from those selling and trafficking those weapons into Baltimore from places outside of our state, to companies who manufacture guns in a way that skirt gun laws in our country.” Scott said he was aware that videos were circulating on social media of the shooting, and repeated Worley’s call for anybody who had one to alert authorities. “When did it become OK for adults to film young people having weapons and no one’s saying anything? We have to be better,” he said. Wes Moore, the Democratic governor of Maryland, expressed condolences and promised action. “My heart breaks for these victims, their families, and the Baltimore community that is coping with the loss. Maryland has had enough of watching gun violence continue to ravage our state and our nation,” he said in a statement. “The fact that these horrific shootings continue to take place is abominable. We as a state will continue to do everything we can to prevent senseless acts of violence like the one we saw last night.” Authorities said the crime scene was extensive and that it will take some time for detectives to work it. MedStar Harbor hospital emergency department treated 19 patients on Sunday, spokesperson Debra Schindler said. Nine critically injured patients were stabilized and transferred to Baltimore trauma centers, and all but one of the others were released. “The hospital went on immediate lock-down to secure the campus and ensure the safety of all patients and associates,” Schindler said in a statement. “Multiple critically injured patients were evaluated and triaged simultaneously by clinical staff, while hospital security managed the throng of family members that gathered.” Other victims were treated at R Adams Cowley shock trauma center and the University of Maryland medical center, spokesman Michael Schwartzberg said. Seven people suffered gunshot wounds and two others needed hospital treatment for trampling in a separate overnight shooting at a nightclub in Kansas, authorities said. Wichita police Lt Aaron Moses told reporters that gunfire erupted at the club on North Washington Street at about 1am, and some patrons were crushed in the rush to escape. Moses said shots were fired from at least four guns, and a person who police believed to be among the shooters was arrested. One of the victims was critically wounded, he said. Elsewhere in the city on Saturday night, authorities reported, a 17-year-old male was shot and killed during an argument with a 21-year-old man. “We have to take actions to push back against this increase in gun violence that we are seeing,” Wichita’s mayor, Brandon Whipple, said. “We have to come together as a community and talk with our young people, in particular about how resorting to gun violence is not the way to solve a problem or issue.” As of Sunday, there had been more than 335 mass shootings in the US so far this year, according to the Gun Violence Archive, which defines a mass shooting as one in which four or more victims are wounded or killed. That high number – more than one daily – has led for many in the US to call for meaningful gun control, though Congress has been unable to enact such measures.