Egypt's journalists' union on Monday condemned provisions contained in a draft counter-terrorism law that impose prison sentences for deliberately publishing "false news or statements concerning terrorist operations" that contradict the official version of events.

The union said the draft law breaches Egypt's 2014 constitution, which bans custodial sentences for most publishing offences.

President Abdel-Fattah al-Sissi vowed to introduce strict new laws to fight terrorism and speed up trials in the aftermath of the death of the country's chief prosecutor. Hisham Barakat was killed in a car bomb attack last Monday.

The bill, which envisages prison sentences of at least two years, comes amid official anger at media coverage of Wednesday's attacks by a local ISIS affiliate on army posts in the Sinai Peninsula.

Many reports gave a much higher toll than the official death toll of 17 soldiers.

Press organizations and rights groups have decried what they say is a crackdown on the media under al-Sissi, who ousted the country's first democratically elected president, Mohammed Morsi, two years ago in the wake of mass demonstrations.

According to the New York-based Committee to Protect Journalists, 18 journalists were behind bars in Egypt as of June 1 because of their work, the highest number since it began keeping records in 1990.