A strong explosion has rocked the Syrian capital Damascus, sending black smoke billowing into the sky, Belfast Telegraph said.

The explosion was in the car park at the Palace of Justice, a compound that houses several courts, said state TV.

Syria has been hit by a wave of massive explosions in recent months, killing dozens of people. Most of the explosions targeted the security agencies of President Bashar Assad, who is fighting to end a 15-month-old uprising against his rule.

Last month, an explosion targeted a military intelligence compound south of Damascus killing 55 people. It was Syria's deadliest blast.

Much of the violence that has gripped Syria since the uprising began has been sanctioned by the government to crush dissent.

But rebel fighters are launching increasingly deadly attacks on regime targets, and several massive suicide attacks this year suggest al Qaida or other extremists are joining the fray.