Protesters threw several home-made grenades at Libya\'s ruling National Transitional Council office in the city of Benghazi on Saturday, without causing casualties, witnesses said. The attack in the eastern city that was the cradle of last year\'s uprising which overthrow Moamer Kadhafi took place as up to 2,000 protesters, including injured former rebels, demonstrated outside the NTC office, witnesses and an AFP correspondent on the scene reported. The explosions came a day before the electoral law and the composition of the election commission is to be announced. At least three blasts were heard by the AFP reporter who said that he did not see any apparent damage to the NTC office or any casualties. Mustafa al-Manae, secretary at the NTC office, said that NTC head Mustafa Abdel Jalil met a group of protesters and also sent three ministers to hear their demands. Witnesses said the blasts occurred when wounded former rebels who helped topple Kadhafi were protesting at being \"marginalised\" in the new Libya, demanding more transparency in the NTC\'s functioning and opposing what they said were opportunists from joining the ruling body. Home-made bombs were used regularly by the former rebels during last year\'s conflict against Kadhafi, especially to attack checkpoints of the former leader\'s forces. Protesters have held regular demonstrations in Benghazi for several weeks, accusing the NTC of lacking transparency and recruiting members who were once seen as loyalists of the former regime. The grenade blasts come just two days after NTC deputy head Abdel Hafiz Ghoga was manhandled by university students in Benghazi. Ghoga, who also serves as official spokesman for the interim government, had to be escorted away after being mobbed by angry students at the University of Ghar Yunis in Libya\'s second largest city. He escaped unharmed but had to endure a tirade of abuse from the crowd, who accused him of opportunism because of his belated defection from the Kadhafi regime. The NTC calling the incident an attack on the Libyan people and the revolution. It said that \"every attack or aggression against the National Transitional Council represents an attack on the sovereignty of the Libyan people and its glorious revolution.\" A statement said Ghoga represents the \"highest legitimate authority\" until the election of a constitutional assembly in June.