The U.S. government has issued a new terror alert for citizens travelling to Europe after the continent played host to four jihadi attacks in just four weeks.

The State Department cited terror attacks in Britain, France, and Sweden as evidence of Islamic State’s ability “to plan and execute terrorist attacks in Europe”.

Stating the threat will heighten during the summer travel season, the U.S. warned “tourist locations, transportation hubs, markets/shopping malls, and local government facilities” are particular targets for jihadis wanting to carry out attacks.

“In addition, hotels, clubs, restaurants, places of worship, parks, high-profile events, educational institutions, airports, and other soft targets remain priority locations for possible attacks,” the State Department noted, warning: “U.S. citizens should exercise additional vigilance in these and similar locations.”

According to the alert, “terrorist sympathisers or self-radicalised extremists” could carry out attacks at any time, with no warning.

It said: “Terrorists persist in employing a variety of tactics, including firearms, explosives, using vehicles as ramming devices, and sharp-edged weapons that are difficult to detect prior to an attack.”

In March, Islamic convert Khalid Masood mowed down pedestrians on Westminster Bridge and stabbed a policeman in a terrorist spree killing five people. And last week, armed police arrested a terror suspect, named as Khalid Mohamed Omar Ali, as he headed towards Downing Street with a bag packed with knives.

Breitbart London reported how Germany has plummeted down to 51st for “safety and security” in the 2017 Travel and Tourism Competitiveness Report, the World Economic Forum’s (WEF) biannual report measuring how “tourism-friendly” economies are. The country now sits between the Gambia and Nepal in the list of 136 countries.

“The overall sense of safety among business travelers across Germany has fallen,” said WEF spokesman Georg Schmitt, who explained that the risk of terrorism is playing on tourists’ minds.

Germany isn’t alone in having experienced a marked decline of its reputation as a safe tourist destination, according to Schmitt.

“Germany has slipped further than most, but the same trend can be seen in almost all western European countries,” he told Die Welt.