Cairo, Oct 27 (IANS): Egypt's President Abdel Fattah Al-Sisi issued a decree Monday allowing military trials for civilians suspected of attacking the country's essential infrastructure, even institutions not belonging to the army, media reported.

The decree came after a deadly attack Friday on an army checkpoint in Sinai that killed 33 soldiers, Xinhua reported citing official news agency MENA.

Sisi promised to take decisive action to combat terrorism, adding the suicide bombing, by a suspected jihadi, was carried out with "external support that wants to destroy Egypt".

The president declared a three-month state of emergency in north and central Sinai, with a curfew from 5 p.m. to 7 a.m.

On Sunday, Sisi gave Prime Minister Ibrahim Mahlab additional powers to act within the context of a state of emergency declared in Sinai.

According to the constitution, Sisi has the legislative power to issue laws, on condition of getting approval from the cabinet, until a parliament is elected.

Militant assaults on security personnel and premises have been growing since the ouster of former Islamist president Mohamed Morsi in July 2013, following a massive security crackdown on his supporters.

The attacks have mostly occurred in the Sinai Peninsula and but also crept into the capital Cairo and other provinces across the country.

On Wednesday, a bomb went off outside Cairo University in central Giza, injuring at least 10 people, including six policemen.

Earlier Sunday, another seven soldiers were killed and four others injured in an explosion that hit their vehicle in Arish city in northern Sinai.

According to the new decree, "the armed forces will join the police in protecting and securing the state's vital and general faculties for two years, and all the crimes committed against those institutions will be referred to military prosecution and eventually military court", said Alaa Youssef, the presidential spokesman.

Youssef said the decree aimed to protect power grids and stations, natural gas pipelines, petroleum fields, railways, bridges and roads against any terrorist attacks.

All those facilities would be treated as military ones and would fall under the jurisdiction of the military, he added, noting that the decision was issued after approval of the National Security Council and the cabinet.