CAIRO, Sept. 26 (Xinhua) -- Organized groups were involved in last week's protests in some Egyptian cities to cause chaos and disorder nationwide, the Egyptian public prosecution said in a statement on Thursday.

The office of Egypt's Public Prosecutor Hamada al-Sawy said that the prosecution questioned about 1,000 defendants who joined the protests in the presence of their lawyers.

"The confessions of some defendants revealed the involvement of criminal elements and others loyal to the Muslim Brotherhood group in those protests," said the statement.

The Muslim Brotherhood was blacklisted in Egypt as a terrorist organization following the military ouster of former Brotherhood-oriented President Mohamed Morsi in July 2013 in response to mass protests against his one-year rule.

The prosecution said that the investigations showed "involvement of some organized groups in planning a plot that targets spreading disorder nationwide through calls for continuous protests to divert them into a non-peaceful course involving acts of violence and sabotage."

It noted that some of the defendants said they joined the demonstrations to protest against their deteriorating economic conditions, while others confessed being deceived by fake social media accounts of government institutions encouraging them to join.

"Other defendants confessed that they met with unknown people in Tahrir Square (in Cairo) urging them to record clips to be broadcasted on anti-state satellite channels to encourage citizens to protest," the statement continued.

Some other defendants said they were football fans who followed rumors about meeting places of fans of Al-Ahly club, which won an Egyptian soccer competition that night, but when they joined they found the crowds shouting anti-state slogans.

"Others stated that they were at the places of protests by coincidence," the top prosecutor's office added.

The statement said that a number of defendants confirmed that protestors committed acts of violence, hurling stones, pieces of glass and fireworks at the police who met them with utmost self-restraint.

Meanwhile, two foreigners were arrested near the places of protests, including a Palestinian Islamist and a Dutch with a camera drone, and the prosecution is currently investigating the reason behind their presence in Egypt, according to the statement.