A keeper has been killed after a female elephant charged at him at a zoo in Missouri.

It is not known why Patience ran at elephant manager John Bradford, who had worked at the Dickerson Park Zoo in Springfield for 30 years.

However, there were reports that the animal, 41, had a history of aggressive behaviour.

"This is very sad day for the zoo family, as well as our community as a whole," said Mike Crocker, director of the zoo.

No other zoo employees were injured in the incident.

It comes just days after the matriarch of the elephant herd Connie was put to sleep.

Officials were forced to euthanise Connie last week after she lost nearly 1,000lbs due to advanced kidney disease and then simply lay down and was unable to get up.

Speaking about 62-year-old Mr Bradford, city spokeswoman Cora Scott said: "He was a very experienced animal manager.

"We haven't had a situation like this happen before."

It was not clear what would happen to Patience, but the zoo said it would remain open on Friday.

Patience has been there since 1990, the Springfield News-Leader reported.

The zoo's elephant herd consisted of three females and two males prior to Connie's death.