The raid, which became a 24-hour running battle, also involved helicopters, the Army and Marines – for whom DETEL provided TETRA radios too. Above flew an aircraft equipped with thermal imaging to locate people on the ground; it could also pinpoint mobile phones and radio transmitters.

“The key word is integration”, he explains. “During these operations, all people use the radios and we use GPS to see the people on the ground. We used all the capacities of the radio for integration between forces.

“Last year our general commander of military police gave us the order to go to Europe and visit six countries in Europe, and after this we visited Israel, to see the best products, the best police force, the best military force, in order to understand the concepts and to use these here.

“We see systems in Spain, in France, in England. But the nearest to our reality is Israel because many enemies are around.”

Vitally important in major operations is the security of the radio signal. The TETRA signal is digital and therefore hard to intercept. But adding encryption makes it almost impossible to penetrate. With Rio’s old analogue radio system, drug traffickers often monitored the police channels. Worse, officers sometimes had to abandon an analogue channel because the criminals were transmitting on it, making fun of them by hurling insults and playing provocative songs.
“We joke between ourselves that you don’t have revolutions in Brazil – or Hawaii, or Australia – because we have many beautiful girls, beaches and beer”, Lt-Col Cajueiro continues, with a smile. “But here in Rio de Janeiro we have problems with criminals, like these problems. Problems in paradise.

“We see drugs in all cities of the world. But drugs with assault weapons, with rifles, with AK47s, maybe only in Rio de Janeiro. Maybe in Colombia, maybe in South Africa. But here you have this kind of numbers.”

On the front line

In the raid on the Complexo do Alemão, engineers from DETEL were right in the front line, visiting the site beforehand as part of their preparations. They were armed, though not in uniform. “Before you begin a military operation, you have to plan where you put your communications gateway, radio base station, repeater”, says Lt-Col Cajueiro. “We used the concepts of Europe, both the Americans and Israel here. When we went to the Complexo do Alemão one week before, we were on the ground, planning where to put it.

“Two days before, we occupied some hills to put our radios before the invasion. Our troops, with DETEL, with the people of CCI (the communications and information technology unit) – they occupied many hills around the German Complex and we studied the radio waves in order to put people in good communication and good coverage.
”It’s a very dangerous situation because we have to be prepared. You cannot attract the attention of the traffickers because you are an inferior number, and the people have weapons of war. To put a little radio in a building, it’s a very dangerous situation.

“In our organization here, we have people from Fire Department, from Police Department, military police, the civilian [police]. These people go to the eye of the hurricane.”

Alongside DETEL staff, engineers from Teltronic Brazil, supplier of the SIRCE network, worked night and day on the technical preparations. They programmed and activated some 130 additional on-board radios for armoured vehicles and motorcycles; prepared and activated a repeater site to improve radio coverage in the conflict zones; created a new radio link between this site and an existing one, and set up gateways to allow communications inside the armoured vehicles.

When the day dawned, the authorities swept in with massive force, in tanks and armoured cars. In photos taken by Lt-Col Cajueiro, it looks like the biggest of Hollywood action spectaculars. In Rio, the Complexo do Alemão had become a kind of black legend, and many hoped to see its evils purged. “It was a special day”, he remembers, with pride. “People put flags in their windows. People saluted us as heroes!

“I interrupted my own vacation to go to the operation. Many people who were off-duty or were at home went to the place. Many old police officers, with white hair or no hair, went to it – ‘I’m here to be against the criminals, to destroy this place! I’m here to contribute!’  It was a very special day.”

Staying alive

Numerous arrests and seizures were made, but police videos also show men fleeing into the surrounding districts. “Many people seeing these images ask us, ‘Why you don’t shoot get these guys?’?”, Lt-Col Cajueiro says, breaking off from his commentary for a moment. “But it’s not the function of a police department. We have to arrest, not to kill people escaping.”
(中国集群通信网 | 责任编辑：陈晓亮)