JOHANNESBURG (Reuters) - The South African detective ridiculed for his slipshod handling of the initial investigation into the killing of Olympic track star Oscar Pistorius' girlfriend has resigned from the force, police said on Thursday.

Warrant Officer Hilton Botha, a detective with 24 years experience, was the first officer on the scene after the Valentine's Day shooting of law graduate and model Reeva Steenkamp.

However, he was pulled off the case after it emerged he was being investigated for seven counts of attempted murder. He was also criticized for mixing up key facts about the investigation at Pistorius' bail hearing.

(Reporting by Peroshni Govender; Editing by Ed Cropley)