Kenyan police say they have arrested a medical intern and an associate who are accused of being part of an Islamic State group extremist cell of medics attempting to launch an anthrax attack in the country.

A statement Monday from the Anti-Terror Police Unit says police on Sunday arrested Mohamed Shukri Yerrow, an intern doctor at Malindi sub-county hospital, along with Abdulrazak Abdinuur following a tip-off from members of the public.

The alleged leader of the cell, Mohammed Abdi Ali, a medical intern in Makueni County, and his wife, a medical student in Uganda, were arrested in May.

Police say two other medics are missing.