Egypt's prosecution ordered the detention of two police officers for investigations into accusations that they killed a lawyer, Karim Hamdy, inside a police station in Cairo's low-income district of Matariya.
The officers belong to the interior ministry's National Security Apparatus which is responsible for investigating terror-related crimes.
The lawyer, who was accused of possessing automatic weapons and involvement in anti-government violence, died soon after questioning by the two officers on Wednesday, reported the Ahram's Arabic news website.
A forensic medicine report said Hamdy sustained fractures to his ribs and suffered from a cerebral haemorrhage.
Last year, an employee of the finance ministry detained at the same station after a domestic fight also died after sustaining similar injuries.
Prosecutors have questioned witnesses and examined the police station.
Preliminary investigations revealed Hamdy was in good health before the questioning, reported Ahram Arabic.
In a statement on Wednesday, Egypt's Lawyers' Syndicate held the police responsible for Hamdy's his death, and called for an immediate investigation into the incident.
The head of the syndicate Sameh Ashour contacted prosecutor-general Hesham Barakat to demand a speedy investigation.
During Hosni Mubarak's era, the National Security Apparatus -- then named State Security Apparatus -- was repeatedly accused of torture.
It was widely regarded as the main security arm protecting Mubarak's regime.
Accusations of torture were also leveled at the police station during Mubarak's rule..