The Sudanese authorities have released all detainees arrested during the protests following a fuel price hike in September, Khartoum's Alahram Alyaoum daily reported Tuesday.

"The security authorities on Monday released the detainees according to directives by President of the Republic Omar al- Bashir," the paper quoted a senior official at the Sudanese Intelligence and Security Service, as saying.

The presidential directive does not cover those facing criminal procedures by the public prosecution and other judicial bodies, the report said.

On Monday, al-Bashir vowed transparent investigations into the killing of a number of protesters during recent demonstrations in Sudan.

"We affirm that the law would be firmly and strongly applied on whoever seeks to undermine the security and stability ... because this is the first and foremost responsibility of the state," said al-Bashir in his address to the parliament on Monday.

"The criminal investigations conducted revealed evidences against 58 suspects who will be brought to trials according to the law and fair judicial procedures," noted al-Bashir.

On Sept. 23, Khartoum and other Sudanese cities witnessed violent protests after the government announced a package of economic reform measures including a fuel price hike.

According to the official statistics, about 70 people were killed during the protests, while international and legal organizations said the deaths that occurred during the demonstrations exceeded 200.