As vacation season heats-up in Europe, the general public particularly those planning to spend their vacation on the beach are being asked to be on the lookout for suspicious-looking people trying to procure necessary items to make chemical, biological or radiological weapons or pose as vendors serving tourists with drinks or beach accessories.

The warnings come as NATO and the European Union both confirmed there are "justified concerns" that the Islamic State (ISIS) is attempting to obtain these weapons to attack Western nations, CBN News reports.

The warnings were issued after intelligence agencies in Italy and Germany claimed that terrorists are planning a Tunisia-style attack on European beach resorts this summer.

"We know terrorists are trying to acquire these substances," Dr. Jamie Shea, deputy assistant secretary general for emerging security threats at NATO, said, referring to ingredients utilised to make chemical weapons.

"There is 'justified concern' that they are looking for even more ingredients for their sinister plots," he said.

Intel reports say terrorists could launch their attacks in some of the most sought-after tourist destinations in the Costa del Sol in Spain, southern France and both coasts of Italy which are also apparently popular spots for British nationals, the Daily Mail reports, citing credible sources.

Undercover operatives in Africa as well as NATO insiders are likewise reporting evidence that the Islamic terror group has "concrete plans" to pose as refugee T-shirt and ice cream vendors and detonate bombs under lounge chairs as well as suicide vests they themselves are wearing, according to CBN News.

They are said to be planning to open fire with automatic weapons as ocean-goers frolic in the surf and sand.

"It could be a whole new dimension of terror. Holiday beaches cannot be protected," a high-ranking British official was quoted by the Mail as saying.

One security expert also said the ISIS threat is likely to "get worse before it gets better."

According to intel reports, the perpetrators will be from the radical Islamic terror group based in Africa known as Boko Haram, which has pledged its allegiance to ISIS.

Seck Pouye, a Senegalese law enforcement official, noted that since these people travel with visas and documents and are viewed as legitimate business people and traders, it would be very difficult and dangerous for law enforcement officers to trace them.