Five men, armed to the teeth, have just stormed a home and it did not go well, not well at all. "You killed a kid!" screamed the instructor.

A glance at the bullet marks on the child-sized mannequin leaves no doubt -- the drill must be repeated.

The men are training at Poland's private European Security Academy (ESA), in the western countryside, which prepares security and military contractors from around the globe for missions in danger zones.

Spread across 100 hectares (250 acres) near the village of Wlosciejewki, the centre is surrounded by fields, woods, lakes and is considered a top-flight choice for future VIP bodyguards, maritime security officers and private military contractors.

"We search out the whole world for the most realistic places to train," said Criss Watts, an instructor from the London-based specialist security company Up Close and Personal (UCP).

"And this is certainly the best place that we consider for our training in the world," he told AFP.

One thing that sets this program apart -- the trainees use real weapons and FX marking cartridges, simulated ammunition that won't kill but feels like the real thing when the trainee fires.

Members of the commando that stormed the dwelling are all working as UCP security operatives. They include a Briton, a Colombian, an Italian and a Spaniard.

- 'ISIS could be on the hill' -

They spent the morning in the Academy's combat village, a full-scale replica of a central section of the Somali capital Mogadishu -- complete with a hotel, coffee shop, bus stop, market and houses painted blue and pink and inscribed with Arabic.

The spring sunshine and windswept sand add a touch of realism to the violent scenarios being acted out.

"In the UK, it's very difficult to train to this standard. In fact, impossible. Can't use pistols for training. You can use weapons on a range but you can't use them for training," said Watts, who spent three decades working in high-risk protection.

"In this centre you can use 762, 9mm, 556, M4, AK47, Glock -- all assortment of pistols and variants," the 49-year-old added, describing a range of guns.

He said UCP's clients pay for them to train at the Academy. "They want to make sure they stay alive. And we want to make sure these guys come back as well, uninjured."

"Anything can happen. ISIS could be on the hill."

Another group trains at a large firing range that includes a 350-metre (380-yard) shooting distance, an area where the men can fire in three directions and a tactical lane allowing them to shoot from moving vehicles.

The course is run by Pawel Brozek, an ESA instructor whose boyish face masks his seven years with Poland's special forces, including several rotations in Afghanistan and Iraq.

"We have trainees from every continent. We train security agents from Saudi Arabia, Bangladesh, Oman, who are on government contracts," he said.

"We also have contractors from protection agencies and individuals who come on their own to get training and find a job."

- Fighting pirates -

Brozek's current group is training to become maritime security officers, highly sought after to safeguard ships and their crews from pirates. Reinforced security has helped curb a wave of hijackings by Somali pirates in the seas off East Africa.

The 26 trainees from nine countries -- Brazil, Colombia, Croatia, Germany, Ghana, Poland, Portugal, South Africa and Spain -- have just completed the first part of their course in the Baltic port of Gdynia.

"It's the realistic aspect that draws people here: the maritime training is done on real boats. All the equipment is the same as what we use at sea," said Brozek.

"We also work with simulators from the Gdynia Maritime School," he added before calling a drill on the bridge of a large roll-on roll-off ship in the port.

Anyone wanting to guard ships has to first obtain a maritime security licence.

This means learning about maritime law and specific procedures: how to use radars, identify a boat, define its speed and distance, communicate with the crew and, of course, take action to prevent a boarding.

"There's a lot of interest in this kind of course," Brozek said.

At around 2,000 euros ($2,250), "it was a little bit expensive" according to Wanderlei Cunha, a 34-year-old trainee who previously served in the Brazilian army's special forces.

"But I saved some money with this objective. So I'm all in. I pushed all my chips on this," he told AFP.

Ervin Cahut, a 40-year-old veteran of Croatia's anti-terrorist military police unit, is also banking on ESA certification, which is recognised around the world.

"I think that some company that needs security guys like me -- ex-military -- to secure a vessel on the sea maybe will take me," he said.