Iran's president on Sunday ordered four Cabinet ministers to lead an investigation into the death of a Canadian photojournalist allegedly beaten into a coma by police for taking pictures of a Tehran (search) prison.

Zahra Kazemi (search), a 54-year-old freelance journalist of Iranian origin, died late Friday in a Tehran hospital after suffering a "brain stroke," an Iranian government official said Saturday in a statement carried by Iran's official news agency.

Canadian officials and Kazemi's relatives and friends say she was arrested June 23 and beaten into a coma while in custody. Friends who visited her in the hospital last week said she was unconscious and had severe cuts and bruises on her face and head.

The Canadian government has demanded answers from Iran concerning the death of Kazemi, who relatives said arrived in Iran after six weeks in neighboring Iraq.

On Sunday, Iranian  President Mohammad Khatami (searchexpressed his sorrow over Kazemi's death and ordered his ministers for culture and Islamic guidance, information, interior, and justice to oversee an investigation, the official Islamic Republic News Agency reported.

"You should determine the reasons for her sudden death and who is responsible for it," IRNA quoted Khatami as saying.

But the Canadian president of Reporters Without Borders (search), which supports international freedom of the press, said she preferred an independent inquiry.

"Any step in that direction is always seen as a positive thing but for us it really is insufficient," Tanya Churchmuch said. "If we were to have some sort of police corps have a prisoner die while in custody, you wouldn't want to have that same police corps investigating itself."

Saturday's government statement did not refer to Kazemi's arrest or detention. Sunday's report said Kazemi suffered a stroke when she was "subject to interrogation" and died in the hospital.

Canadian Prime Minister Jean Chretien (searchexpressed his sympathy to Kazemi's family on Sunday. Canada's ambassador to Iran is expected to meet with Iran's foreign minister about Kazemi's death, Canadian officials said.

Iranian officials have said that Kazemi was authorized to cover last month's violent pro-reform protests in Tehran.

Club and knife-wielding hard-line vigilantes aligned with Iran's supreme leader, Ayatollah Ali Khamenei, battled with students and bystanders during the June 10-14 protests, predominantly in Tehran.