Two people were killed and six injured by a gunman who opened fire in a high-rise office building in Orlando, Florida on Friday, local media reported.

A police spokeswoman said there were multiple victims in the shooting at the Gateway Center in downtown Orlando, but she could not immediately confirm any fatalities.

The Orlando Sentinel newspaper and local TV networks reported that two people had been killed.

Police evacuated the building and said the gunman was still at large.

The Orlando Sentinel said bodies were found on the 12th and 8th floors of the building.

"I can confirm to you that we have multiple victims - I'm not going to give you the number, or status -- that were taken to local hospitals," said Sergeant Barbara Jones.

She said the suspected gunman was reported to be a former employee of a company with offices in the building.