Rights advocates accuse veteran President Ilham Aliyev's government of muzzling dissent and jailing opponents, charges it denies. The West has courted the former Soviet republic as an alternative to Russia in supplying oil and gas.

Ismailova has been critical of the president and some members of the government.

The court ordered that she be held in pre-trial detention for two months after a former colleague at the radio station attempted to kill himself.

If convicted, she could face up to seven years in prison.

Her lawyer said the ruling was "absurd".

"Prosecutors don't have any evidence. We plan to appeal the court's decision," Elton Guliyev said.

Europe's main security and rights watchdog condemned the arrest and said it was the latest case of a crackdown on media freedom in Azerbaijan.

"The arrest of Ismailova is nothing but orchestrated intimidation, which is part of a campaign aimed at silencing her free and critical voice," Dunja Mijatovic, media representative of the 57-nation Organisation for Security and Cooperation in Europe (OSCE), said in a statement.

Several other journalists and human rights defenders were sentenced to prison terms earlier this year on charges including tax evasion, illegal business activity and hooliganism. Defence lawyers called the charges unfounded and politically motivated.

Azerbaijan, a mainly Muslim former Soviet republic, says its 9 million citizens enjoy full freedom of speech and a lively opposition press.