At least 25 people were killed in a suicide bomb attack at a court house in Damascus on Wednesday, state media reported, the second bomb attack in the Syrian capital in five days.

The attack targeted the Palace of Justice in central Damascus not far from the Old City. State news agency SANA said there were a "number of wounded" in addition to the initial death toll of 25.

The bomber set off his explosive device after the police tried to stop him from entering the building, Ahmed al-Sayyid, a senior state legal official told al-Ikhbariya TV.

On Saturday, scores of people, most of them Iraqi Shi'ite pilgrims, were killed in a double suicide attack in Damascus claimed by an alliance of jihadist groups known as Tahrir al-Sham.