Protesters have taken to the streets in Minneapolis, in the state of Minnesota, after a United States Border Patrol agent killed a US citizen, heightening tensions in a city already shaken by a deadly shooting just weeks earlier of a mother of three.

Minneapolis police chief Brian O’Hara told reporters that a 37-year-old man, a Minneapolis resident, died in hospital on Saturday after being shot multiple times.

Family members identified him as Alex Pretti, an intensive care unit nurse who had previously protested against President Donald Trump’s immigration crackdown in the city.

After the shooting, an angry crowd gathered, and protesters clashed with federal officers, who wielded batons and deployed flashbang grenades.

The Minnesota National Guard was assisting local police at the direction of Governor Tim Walz, officials said. Guard troops were sent to the site of the shooting and to a federal building where officers have been facing off with demonstrators on a daily basis.

Department of Homeland Security spokesperson Tricia McLaughlin said in a statement that federal officers had been conducting an operation and fired “defensive shots” after a man with a handgun approached them and “violently resisted” when they tried to disarm him.

In bystander videos of the shooting that emerged soon afterwards, Pretti is seen holding a mobile phone, but none appears to show him with a visible weapon.

Pretti was shot about 1 mile (1.6km) from the spot where an ICE officer killed 37-year-old Renee Good on January 7, which led to widespread protests.