Israel is concerned that Islamic State terrorists facing defeat in the Middle East are heading back to their home countries and may try to carry out attacks in the near future, including a possible chemical attack in Europe, Channel 2 TV news reported Thursday.

The report said Israel’s Counter-Terrorism Bureau is poised to issue a series of travel warnings ahead of next month’s Passover holiday calling on Israelis traveling to Western Europe, India and Thailand to exercise extreme caution.

The TV report stressed that warnings have not yet been issued.

Sources in the bureau told Channel 2 that the Islamic State’s recent defeats in Iraq and Syria are causing many jihadis to return to their countries of origin.

These well-trained fighters could attempt to carry out vehicle-ramming attacks similar to the truck attack in Berlin that killed 12 people, including Israeli Dalia Elyakim, on Christmas.

Officials particularly fear terrorists may attempt to carry out a chemical attack against civilians, using widely available substances. Chemical bombs can be manufactured from products readily available in supermarkets, the report noted.

The bureau will soon formally call on Israelis traveling abroad to be alert, especially in crowded locations, and to pay attention to anything unusual, the report said.

The Israeli warning would echo guidance issued by the US State Department on Tuesday telling travelers worldwide to be especially careful of less-sophisticated terror attacks as well and warning of an growing likelihood of non-conventional attacks.

“Terrorists are increasingly using less sophisticated methods of attack to more effectively target crowds,” said the warning, “including the use of edged weapons, pistols, and vehicles as weapons.”

The State Department also warned that terrorist groups “including ISIS, al-Qa’ida, their associates, and those inspired by such organizations, are intent on attacking US citizens wherever they are.”

“Extremists may use conventional or non-conventional weapons,” it said, and cautioned that potential “soft” targets include “high-profile public events (sporting contests, political rallies, demonstrations, holiday events, celebratory gatherings, etc.); hotels, clubs, and restaurants; places of worship; schools; parks; shopping malls and markets; tourism infrastructure; public transportation systems and airports.”