COPENHAGEN (Reuters) -A fire that broke out on Thursday morning at Denmark's tax ministry in central Copenhagen, which sent a plume of thick, black smoke into the air, has largely been extinguished and no one was injured, the city's fire department said.

"We are still having minor fires (on) the roof but we've handled the situation and the fire is not spreading anymore," Copenhagen fire department incident manager Tim Ole Simonsen told Reuters.

It was not immediately clear what caused the fire, Simonsen said, adding that police would investigate.

The blaze comes after Copenhagen's old stock exchange, a 10-minute walk from the tax ministry, was toppled by fire in April.

The tax ministry office complex was evacuated, along with other nearby buildings, according to police.

"Everybody is safe and nobody is hurt," Simonsen said.

Tax minister Jeppe Bruus told Reuters he was in a meeting when the fire broke out and that the emergency services responded promptly.

"The alarm went off and I went outside the meeting room and I could immediately smell the smoke from the fire. So I got my bag and got out of the building," Bruus said, adding that the process was calm.

"When we got out, we could see the flames on the top of the building," he said. "Once we got out of the building we could already hear the sirens of the fire trucks arriving very fast."

(Reporting by Isabelle Yr Carlsson and Louise Breusch Rasmussen, editing by Terje Solsvik and Bernadette Baum)