Random shells hit Thursday several residential areas in the Yemeni capital as deadly clashes entered the fifth consecutive day between government forces and the defected army, killing dozens of people and injuring scores of others, residents said.

The country's Defence Ministry said that four civilians were killed by shelling on a residential area near the state television by the defected army backed by tribesmen.

It said the shells also hit Misaik residential quarter near the building of the U.S. embassy in western Sanaa.

The ministry added that the ongoing shelling by the defected army on a military camp belonging to the Republican Guards, the country's elite troops led by President Ali Abdullah Saleh's elder son Ahmed Ali, injuring more than 15 soldiers.

An official of the Interior Ministry told Xinhua on condition of anonymity that the residential compound of pro-government tribal leader Sagheer bin Aziz was destroyed and five of his followers were killed and up to 14 others were injured.

Meanwhile, local residents and eyewitnesses told Xinhua that dozens of civilians and tribal fighters were killed and more than 20 others injured in heavy shelling by the Republican Guards on residential areas located between a defected military base and the headquarters of the Yemeni state television station in northern Sanaa.

At least 20 mortars hit houses in residential neighborhoods of Hail, Al-Dairy, Al-Zira'aa and Al-Zubairi, which all located around the Kintaki area near the protester's sit-in square in southern Sanaa.

Initial medical reports said that dozens of civilians were injured without mentioning the death toll.

In Hassaba district in downtown the capital, where at least 11 government departments located, residents told Xinhua that several random Katyusha rockets hit a mosque and destroyed eight houses, injuring at least 15 civilians.

Earlier, medics told Xinhua that at least five protesters were killed by government snipers on rooftops and 10 others were injured in clashes on Thursday morning.

The fresh deadly fight came a day after the Gulf Cooperation Council (GCC) chief Abdullatif al-Zayani left Sanaa failing to calm down the situation.

Saleh, who has backed out from signing the GCC deal for three times, is still in Saudi Arabia for rehabilitation from injuries he sustained in an attack on his palace in early June.

Yemen has been gripped by political crisis since protests erupted across the country in late January, which demanded an immediate end to the 33-year rule of Saleh.