The situation in Syria is turning into bloody civil war. The Syrian army, under orders from President Bashar Assad, has continued to shell villages indiscriminately. The shelling, sniping and bombing of cities and villages has brought widespread condemnation from the world, yet still no direct action has been taken.

Pope Benedict XVI has called for urgent humanitarian aid to reach residents and demanded that those responsible for the bloodshed end it, warning that continued violence will have “strongly negative consequences for the country and entire region”.

The Vatican had been relatively silent at the start of the uprising against President Bashar Assad’s regime, mirroring the general sentiment of Syrian Christians who largely stuck by Assad out of fear of the Muslim hard-liners in the uprising against his rule.

But the landscape is changing. In an incident reminiscent of what happened in Malta during the Libyan uprising against Muammar Gaddafi, a Syrian fighter plane has landed at a military air base in the north of Jordan and the pilot has asked for asylum.

Syrian state TV said a fighter plane – a Mig 21, flown by an air force colonel – had gone missing during a training mission.

The Russian-made Mig landed at the King Hussein Air Base in Mafraq, close to the Syrian border. A spokesman for the rebel Free Syrian Army, Ahmad Kassem, said the group had encouraged the pilot to defect.

In the meantime, the cradle of the Arab Spring, Tunisia, has a long history of frustrated youth heading off to fight in foreign jihads. Now, according to figures released by the Syrian government, they may make up a large percentage of Arabs who have gone to join the struggle against the regime of Bashar Assad. And that has raised alarm both about radicalisation in the Syrian rebel movement, and of rising extremism within newly-democratic Tunisia itself.

It is an awkward situation for the Tunisian government, which has to rely on international organisations to follow up on the fate of its citizens arrested in Syria, since it was one of the first countries to cut ties in protest of the regime’s brutal crackdown on the opposition.

It is not known how many Tunisians have gone to fight in Syria. Al-Qaeda-style suicide bombings have become increasingly common in Syria, and Western officials say there is little doubt that Islamist extremists, some associated with the terror network, have made inroads in Syria as instability has spread. But the main fighting force looking to oust Assad is the Free Syrian Army, a group made up largely of defected Syrian soldiers.

The Syrian government maintains that they are fighting foreign jihadists and in mid-May issued a letter to the United Nations giving the name of 26 arrested jihadists and alleged members of al-Qaeda. Nineteen of them were Tunisian.

With the advent of radical Islamists in Syria, there is a very real risk that the country could just collapse. Even if the Syrian rebels do manage to topple the Assad regime, it could just make matters worse as sectarian violence spreads due to radicalisation. The longer the world leaves it, the worse the situation is going to get.