Twin shootings in Rotterdam on Thursday have resulted in an unknown number of fatalities, police said.

A gunman dressed in combat gear opened fire in a flat in the Dutch city then burst into a nearby medical centre. Fires broke out in both places but were later extinguished.

"The two shooting incidents in Rotterdam have resulted in fatalities. We will first inform family and relatives and will explain more later," the city police said in a statement on X, formerly Twitter.

Elite police units had burst into the hospital in the Dutch city searching for the suspect, who was armed with a handgun, authorities said.

The suspect is 32 and the motive for the attack is unknown, local news agency ANP said, citing police. He is suspected of carrying out both shootings and there is not a second shooter, police said.

Pictures from the scene showed people streaming out of the hospital, including medics and patients, as police in body armour moved in. Police helicopters buzzed overhead.

Medics in white coats wheeled patients out on stretchers and wheelchairs 

Police had earlier said the suspect was wearing "combat-style" clothes, was tall, with black hair and carrying a backpack.

"First there was a shooting on the fourth floor. Four or five shots were fired. Then a Molotov cocktail was thrown into the education centre," said a medical student cited by RTL Nieuws, who did not give his name.

"There was a lot of panic and screaming... I didn't hear any shots, just the panic and that's what I started to act on," public broadcaster NOS cited another eyewitness as saying.

Rotterdam is often the scene of shootings, usually attributed to score settling by rival drug gangs.

Authorities were expected to hold a news conference shortly to give more details.

In 2019, three people were shot dead on a tram in Utrecht, sparking a huge manhunt.

And in 2011, the country was left shocked when 24-year Tristan van der Vlis killed six people and wounded 10 others in a rampage at a packed shopping mall.

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