After killing 47 worshippers at churches in two cities in Egypt a little over a week ago, the terrorist group struck again on Tuesday, this time in the tourist hotspot of southern Sinai.

IS claimed responsibility for the exchange of fire at a police checkpoint about 800 metres away from the UNESCO heritage-listed ancient site of St Catherine's Monastery which killed a policeman and injured four others.

The attack came hours after Sisi met with an Iraqi delegation to discuss counter-terrorism efforts.

IS has been steadily losing its territorial stronghold in Mosul, since coalition forces launched an operation to retake Iraq's second largest city six months ago, and analysts say it may be seeking a stronger presence in Egypt.

"It does seem that the group is investing more time and resources towards Egypt and Sinai in particular," Mokhtar Awad, research fellow at the Program on Extremism at George Washington University, tells Fairfax Media.

"After the fall of Sirte [in] Libya, Sinai is the Islamic State's only somewhat successful venture in North Africa," he says.

A media gag and a three-month state of emergency in the Sinai obfuscate how military operations are proceeding but Egypt's military intelligence chief estimated in February that more than 500 militants have been killed in the past two years in counter-terrorism operations.

Yet, that has not halted IS from branching into the peninsula and specifically targeting Coptic Christians, who make up around 12 per cent of the population and are the largest religious minority in the Middle East at around 10 million.

On Wednesday Egyptian police said it had tracked down and killed a gunman suspected of involvement in the St Catherine's Monastery attack.

"The Egyptian military is still slowly adapting to the new type of asymmetric threat jihadists pose [???] they need to develop a comprehensive counter-insurgency strategy," Awad says.

In February, dozens of Coptic Christian families were forced to leave their homes in northern Sinai after a spate of targeted killings. IS released a video in the same month vowing to continue its attacks on Copts. In December, it bombed the church adjoining the cathedral in Cairo killing 28 people.

The latest attack will deal another blow to Egypt's economy that is in urgent need of foreign currency generated by tourism. The latest figures from the Egyptian Tourist Authority show 5.3 million tourists entered the country in 2016 compared to 9.3 million in 2015, with Russia, Ukraine and Britain among top origin countries.

The drop reflects the scare after a Russian plane crashed in the Sinai in October 2015 killing all 224 passengers and crew - an attack also claimed by IS.

Israel, a popular source of tourism, warned its citizens last month to leave holiday resorts in the Sinai because IS and other militant groups were posing a credible threat.

The attack near the monastery could have been deadlier and raises further questions about Sisi's mandate, who ascended to power from the ranks of the military by promising to "eradicate terrorism in northern Sinai".

Sisi's next steps will determine Egyptians' confidence in his ability to steady the country, as well as determine if IS will remain a burgeoning threat in the rugged peninsula.