Police beat journalists who were covering demonstration in Amman [AFP]

Jordan's criminal investigation department (CID) has formed a panel to inquire into the attacks on journalists by police at a demonstration in Amman a day earlier.

"General Hussein Majali has formed a committee of inquiry into the attacks on the journalists who were simply doing their jobs," CID chief said in a statment on Saturday.

Majali's department said it would "announce the results of the investigation within the next 72 hours and refer to the courts those who have a case to answer."

"So far, four police officers suspected of being linked to the attacks on journalists have been arrested," the statment said.

At least 17 people, including journalists and policemen, were injured on Friday when police tried to stop clashes between pro-reform demonstrators and government supporters in central Amman, the Jordanian capital.

Police used batons to break up the clashes outside city hall, beating and injuring 10 journalists who were wearing orange vests marked "Press".

An Al Jazeera correspondent and several other journalists, including a Reuters cameraman, said they were attacked by the police.

The wounded included an AFP photographer and a female activist.

'Rampant corruption'

Besides Amman, rallies for reform and against "rampant corruption" also took place in Tafileh, Man and Karak in the country's south, and in Irbid and Jerash in the north.

Our correspondent Nisreen El Shamayleh said there is a definite feeling in Jordan that there is no serious motivation to implement real and true democratic reforms in the country.

Security forces had previously prevented demonstrators from assembling at main squares.

They have been demanding the removal of the government, but not King Abdullah, who appoints the cabinet and has wide powers.

The clampdown appears to have been prompted by fears of mass crowds as seen in Egypt and Tunisia, where long-serving leaders were overthrown earlier this year.

Jordan has faced a protest movement demanding political and economic reforms, and an end to corruption since January.