WARSAW, Poland: The gunman who allegedly killed six people and wounded 16 more in a mass shooting in the main square of the Polish city of Krakow on Saturday has died in hospital. The man had been shot by police in their attempts to arrest him.

The attack took place in Krakow's historic centre, Poland's second-largest city and a major tourist destination. Police began receiving reports at around 3 p.m. Saturday local time that a gunman was firing randomly at people from a car.

Two police officers were among those injured. They were hurt during a shootout with the attacker, who was wearing military-style clothing, according to police.  The alleged shooter was named as Michael Oksinski, 24. 

Officers said they used their weapons while attempting to arrest the suspect, but he returned fire. The gunman was eventually shot by police and taken to hospital for treatment, where he died on Monday, after undergoing a number of operations.

Fifteen of the 16 people wounded are said to be in a stable condition. The two injured police officers have since come out of comas.

Unverified videos shared on social media showed people running away as gunshots and police sirens could be heard. Other footage appeared to show injured people lying on blood-stained paving stones, while bystanders attempted to revive them.

A witness named only as Konrad told news website Interia that he had seen the shooting from nearby.

He said, "I saw shots being fired from the driver's side window, and smoke was coming out."

He added that he ran into a police station in the main market square, where several people had taken shelter on the floor.

The shooting prompted a response from Poland's political leaders, with Prime Minister Donald Tusk saying he was receiving regular updates about the incident.

The attack occurred in Krakow's historic centre, a UNESCO World Heritage Site that attracts large numbers of visitors.

Police confirmed on social media at the time that the suspect had been shot during the arrest and was being transported to hospital.

President Karol Nawrocki expressed sympathy for those affected by the shooting and their families. He said his thoughts were with the victims and everyone impacted by the attack.