A grenade reportedly smuggled into a Colombia prison by a woman hiding it in her body exploded killing five inmates.
The device went off on Tuesday night after it was brought into the Villa Hermosa jail in the city of Cali.
Prison officials said inmates were handling the grenade when it exploded. Three died instantly - two later in hospital - and 20 were wounded.
One official was quoted as saying a woman, visiting an inmate, concealed the grenade inside her vagina.
Prison spokeswoman Lina Maria Hoyos said guards were not allowed to inspect female visitors' genitals.
The woman left the prison without being caught, the official was quoted by Reuters news agency as saying.
Colombia's jails have a reputation for violence and anarchy.