DAMASCUS - Explosions and attacks continued to rock Syria over the weekend, as the international community keeps on mediation efforts in a bid to end violence and bloodshed.

Three mortar shells landed near government buildings in Damascus on Sunday. No casualties were reported.

Meanwhile, the rebels "ferociously" stormed a police academy in the northern province of Aleppo, killing tens of government troops, according to the al-Khabar TV.

Rebels have tried in recent months to overrun military bases in northern Syria, but the state media said that the government troops have secured several towns along the major roads leading to Aleppo.

On the government side, Syrian President Bashar al-Assad said in an interview that he could not think of living outside his country, noting that he was ready "to negotiate with anyone, including militants who surrender their arms".

The embattled leader made the remarks as US Secretary of State John Kerry renewed calls for him to step down, saying in the last week that he was drafting diplomatic proposals about ways to "ease Assad out (of power)".

The visiting US top diplomat talked on Saturday in Cairo with Arab League (AL) Secretary-General Nabil al-Arabi on the Syria crisis, hoping to put an end to the country's escalating violence.

In addition, Israel has launched military actions against Syria to thwart direct threats against its security, Strategic Affairs Minister Moshe Ya'alon said Sunday, referring to alleged Israeli air strikes on the Israeli-Syrian border and near Damascus over the past months.

For his part, Iranian President Mahmoud Ahmadinejad said in Tehran Saturday that only national dialogue is a "logical" solution to the Syria crisis. He called for an immediate cessation of violence and foreign intervention in the Arab state.

Iranian Foreign Minister Ali-Akbar Salehi also said on the same day that Assad will take part in the presidential election in 2014.

Also on Saturday, UN chief Ban Ki-moon and UN-AL Joint Special Representative Lakhdar Brahimi said in a joint statement that the UN will be prepared to facilitate a dialogue between the Syrian government and the opposition.

They expressed "deep frustration at the failure of the international community to act with unity to end the conflict" and stressed the necessity of the unity of the international community, according to the statement.

As the security situation in Syria deteriorates, the Iraqi security forces on Sunday blocked a border crossing point with Syria, a day after the Syrian rebels seized the other side of the crossing from the Syrian government troops, an Iraqi security source said.

Meanwhile, Royal Jordanian Airlines has changed the route of its operations between Amman and Beirut from March 2 to avoid the Syrian conflict and protect the safety of passengers, a company statement said Sunday.