Cairo: Egyptian soldiers and police stormed pro-democracy offices on Friday, targeting groups critical of the military rulers while reinforcing activists' charges that the military's harsh tactics are no different from those of the deposed regime of Hosni Mubarak.

Among the offices ransacked by police were well known US-based organisations like the International Republican Institute, which is observing Egypt's ongoing parliamentary election process. IRI issued a statement denouncing the raid, as did reformers and rights groups.

The raids on 10 non-governmental organizations were part of an investigation into foreign funding of rights groups, the Egyptian Interior Ministry said. Egypt charges that foreign plots are behind the ongoing protests.

The crackdown was sure to inflame almost constant protests in downtown Cairo, demanding that the ruling military that took over after Mubarak in February hand over power to a civilian authority after more than 60 years in power.

A leading Egyptian reformist Mohamed ElBaradei, a Nobel peace laureate, denounced the raids.

"Human rights organisations are the guardians of nascent freedom. Efforts to suffocate them will be a major setback and will surely backfire," ElBaradei wrote on his Twitter account.

Also likely to inflame protests, an Egyptian court on Friday acquitted five policemen of charges of killing five protesters and wounding six others during the 18-day uprising that toppled Mubarak's regime February 11.

More than 800 protesters were killed in the demonstrations that began January 25.

The court said three of the defendants were not at the site of the killings while the two others fired against protesters in self defence.

Protesters have demanded that security forces who killed demonstrators be brought to justice along with those who gave orders to open fire.

Mubarak himself is on trial on charges he was involved in the killing of protesters in the uprising. He could face the death penalty if convicted.

During the uprising and since Mubarak's ouster, Egyptian authorities have complained about unspecified foreign attempts to destabilise the country.

Egypt, like other Arab states, has a long history of blaming internal problems on foreign saboteurs.

The raids on the NGO's were the first since Mubarak's ouster, though Egyptian officials have been levying accusations for months that rights groups are serving a foreign agenda.