Israel has warned citizens visiting the Sinai Peninsula to leave the area immediately and those planning on visiting to change their plans over fears of attacks coinciding with Wednesday’s anniversary of Egypt’s 2011 uprising.

Prime Minister’s Benjamin Netanyahu’s counterterrorism office said there was a “very high concrete threat level” on the sixth anniversary of the uprising that toppled President Hosni Mubarak.

Unlike past Jan. 25 anniversaries marred by deadly clashes between police and protesters, this one has been mostly quiet, with the deployment of a larger-than-usual number of security forces in Cairo and elsewhere in the country.

Sinai, with its pristine beaches and Red Sea coral reefs, is a popular tourist destination. However, the northern part of the strategic region has for years been home to an insurgency dominated by Islamic militants, who have carried out occasional attacks on tourist sites in the south that are frequented by Israeli and other tourists.

There has not been a major attack in southern Sinai since October 2015, when a Russian airliner crashed soon after taking off from the Red Sea resort of Sharm el-Sheikh, killing all 226 people on board. The Islamic State group, whose local affiliate is active in northern Sinai, said it downed the aircraft with an explosive device planted on board.

The Israeli travel warning, which is an upgrade on routine security advisories, follows the departure in mid-December of the Israeli ambassador in Egypt and his staff over security concerns.

Cairo airport officials say the ambassador, David Govrin, and his staff routinely fly home on Thursdays and return to their post on Sunday. However, they have not been back since they left last month.

Egyptian security officials said the embassy had informed authorities in Cairo that it had received intelligence suggesting that there was an imminent security threat to its personnel. The officials said the embassy did not divulge details of the threat, and that Egyptian authorities did not have similar intelligence of their own.

The officials spoke on condition of anonymity because they were not authorized to brief the media.

The Israeli Foreign Ministry has declined to comment.

(AP)