Chicago, Apr 11 (IANS): Four people were killed and nine others injured in a shooting that happened in downtown Louisville in the US' Kentucky state.

Of the injured, three were in critical condition. One of the two police officers injured was in critical condition, Louisville police confirmed in a news conference, Xinhua news agency reported.

Louisville police made to the scene in three minutes. The police said that the suspect, 23-year-old white man Connor Sturgeon, shot at officers, and the police returned fire and "stopped that threat".

The gunman worked at the bank, Louisville Interim Chief Jacquelyn Gwinn-Villaroel said at a news briefing Monday afternoon.

There was a heavy police presence at the scene, with damaged glass and discarded medical equipment at one location, local media reported.

The incident started around 8:30 a.m. Monday at the Old National Bank on the E. Main Street, the Louisville Metro Police Department tweeted.

Gunshots could be heard on video clips at the scene posted on social media.