Spanish police say they have arrested an American woman who had been threatening to kill famed British physicist Stephen Hawking while he was in Spain for an astronomy conference.

A police statement Friday said the woman was arrested in a hotel near where a conference being attended by Hawking was being held on Spain's Canary Island of Tenerife this week.

Police said the woman had been following Hawking and had recently sent him emails and posted messages on social media threatening to kill him at the conference center. Police said the woman, 37, who was not identified by name, may suffer from mental problems.