Several thousand people have participated in street protests in Montenegro. The demonstrators on Sunday demanded the resignations of top security officials over a shooting earlier this week that left 12 people dead including two children.

Thousands of Montenegrins gathered in the town of Cetinje on Sunday to commemorate the 12 victims of a mass shooting last week, with many accusing police of not having done enough to stop the gunman's rampage.

The New Year’s Day shooting shocked a country where gun ownership is widespread. Montenegro’s government began a three-day mourning period Thursday after a gunman opened fire on New Year’s Day — killing 12 people, including two children, across several locations.

A commemoration ceremony was held in the small Montenegrin town of Cetinje on Saturday for the 12 victims of a New Year's day shooting. The ceremony was attended by family members of the victims as well as political and church leaders.

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The government has declared three days of national mourning from Thursday, with Prime Minister Milojko Spajic saying the shooting had "shrouded our country in black". Police said the attack began at 17:30 local time (16:30 GMT) when a man - named as Aleksandar Martinović, 45 - opened fire in the restaurant.