CAIRO: Former Arab League head and likely candidate for the Egyptian presidency Amr Moussa said today that the Egyptian government must launch a formal investigation into last night's clashes in Cairo's Abbaseya neighborhood. More than 300 people were injured when a peaceful march from Tahrir Square to the Ministry of Defense was attacked in Abbaseya. The march intended to put pressure on Egypt's ruling military regime and demand an end to military trials of civilians. Moussa expressed regret that the incidents occurred via his personal Twitter account. He said the right to safe, peaceful protest is one of the gains of Egypt's January 25 Revolution and should be protected, as should all forms of expression.