The US is now hunting for Walter Palmer

The White House is now considering the extradition of Walter Palmer over the killing of Cecil the lion, while American wildlife authorities have urged him to contact them immediately.

More than 160,000 people (and counting) have signed a petition urging the dentist from Minnesota to be extradited to Zimbabwe - past the 100,000 signatures in 30 days threshold that guarantees a White House response.

The US fish and wildlife service (FWS) said it was "deeply concerned" by Cecil's death - he was a collared lion living on protected land - but had been unable to contact Palmer, who has closed his dental practice in Minneapolis and apologised to patients for the disruption.

It is up to all of us - not just the people of Africa - to ensure that healthy, wild populations of animals continue to roam the savannah for generations to come.

• FWS statement

Two Zimbabwean men have already appeared in court over Cecil's death but White House spokesman Josh Earnest said it was up to the justice department to handle any extradition issues.

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